[ci skip]

Curved lines at top of pipeline graph

#### What does this MR do?
Adds curved lines to second-child of each column
## Are there points in the code the reviewer needs to double check?

#### Why was this MR needed?
To match the mockup

#### What are the relevant issue numbers?
Closes #21126 

#### Screenshots (if relevant)
![Screen_Shot_2016-08-26_at_9.31.49_AM](/uploads/318d3df4ce909daa0ef8ea8d989211c4/Screen_Shot_2016-08-26_at_9.31.49_AM.png)

See merge request !6033

Add horizontal scrolling to all sub-navs on mobile viewports

## What does this MR do?
Adds horizontal scrolling to all the sub navigation on mobile views. This was previously only available on the repository tab (commits page). 

## Are there points in the code the reviewer needs to double check?
Perhaps a better way to refactor out the common haml code

## Why was this MR needed?
Adding it to all to keep the UI consistency and to offer mobile users a better interface

## What are the relevant issue numbers?
Closes #20779 

## Screenshots (if relevant)
Before:
![Screen_Shot_2016-08-23_at_3.52.35_PM](/uploads/3833da4252cf616266a77654cee89faf/Screen_Shot_2016-08-23_at_3.52.35_PM.png)

After:
![Screen_Shot_2016-08-23_at_3.52.21_PM](/uploads/5a023bb1e639f16f2471009dd6ae0d62/Screen_Shot_2016-08-23_at_3.52.21_PM.png)

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- Tests
  - [x] All builds are passing
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !5762

Reduce contributions calendar data payload

## What does this MR do?
Reduces the contributions calendar data payload by only passing contribution dates and counts

## Are there points in the code the reviewer needs to double check?
Please double check my javascript code :smiley: 

## Why was this MR needed?

Reduce user's bandwidth and decrease website loading time

## What are the relevant issue numbers?
Closes #20862 

## Screenshots (if relevant)
Before:
![Screen_Shot_2016-08-11_at_3.55.55_PM](/uploads/382842b3c889978bb302bd9057701ec3/Screen_Shot_2016-08-11_at_3.55.55_PM.png)
```
new Calendar(
  {"1439269200":0,"1439355600":0,"1439442000":0,"1439528400":0,"1439614800":0,"1439701200":0,"1439787600":0,"1439874000":0,"1439960400":0,"1440046800":0,"1440133200":0,"1440219600":0,"1440306000":0,"1440392400":0,"1440478800":0,"1440565200":0,"1440651600":0,"1440738000":0,"1440824400":0,"1440910800":0,"1440997200":0,"1441083600":0,"1441170000":0,"1441256400":0,"1441342800":0,"1441429200":0,"1441515600":0,"1441602000":0,"1441688400":0,"1441774800":0,"1441861200":0,"1441947600":0,"1442034000":0,"1442120400":0,"1442206800":0,"1442293200":0,"1442379600":0,"1442466000":0,"1442552400":0,"1442638800":0,"1442725200":0,"1442811600":0,"1442898000":0,"1442984400":0,"1443070800":0,"1443157200":0,"1443243600":0,"1443330000":0,"1443416400":0,"1443502800":0,"1443589200":0,"1443675600":0,"1443762000":0,"1443848400":0,"1443934800":0,"1444021200":0,"1444107600":0,"1444194000":0,"1444280400":0,"1444366800":0,"1444453200":0,"1444539600":0,"1444626000":0,"1444712400":0,"1444798800":0,"1444885200":0,"1444971600":0,"1445058000":0,"1445144400":0,"1445230800":0,"1445317200":0,"1445403600":0,"1445490000":0,"1445576400":0,"1445662800":0,"1445749200":0,"1445835600":0,"1445922000":0,"1446008400":0,"1446094800":0,"1446181200":0,"1446267600":0,"1446354000":0,"1446444000":0,"1446530400":0,"1446616800":0,"1446703200":0,"1446789600":0,"1446876000":0,"1446962400":0,"1447048800":0,"1447135200":0,"1447221600":0,"1447308000":0,"1447394400":0,"1447480800":0,"1447567200":0,"1447653600":0,"1447740000":0,"1447826400":0,"1447912800":0,"1447999200":0,"1448085600":0,"1448172000":0,"1448258400":0,"1448344800":0,"1448431200":0,"1448517600":0,"1448604000":0,"1448690400":0,"1448776800":0,"1448863200":0,"1448949600":0,"1449036000":0,"1449122400":0,"1449208800":0,"1449295200":0,"1449381600":0,"1449468000":0,"1449554400":0,"1449640800":0,"1449727200":0,"1449813600":0,"1449900000":0,"1449986400":0,"1450072800":0,"1450159200":0,"1450245600":0,"1450332000":0,"1450418400":0,"1450504800":0,"1450591200":0,"1450677600":0,"1450764000":0,"1450850400":0,"1450936800":0,"1451023200":0,"1451109600":0,"1451196000":0,"1451282400":0,"1451368800":0,"1451455200":0,"1451541600":0,"1451628000":0,"1451714400":0,"1451800800":0,"1451887200":0,"1451973600":0,"1452060000":0,"1452146400":0,"1452232800":0,"1452319200":0,"1452405600":0,"1452492000":0,"1452578400":0,"1452664800":0,"1452751200":0,"1452837600":0,"1452924000":0,"1453010400":0,"1453096800":0,"1453183200":0,"1453269600":0,"1453356000":0,"1453442400":0,"1453528800":0,"1453615200":0,"1453701600":0,"1453788000":0,"1453874400":0,"1453960800":0,"1454047200":0,"1454133600":0,"1454220000":0,"1454306400":0,"1454392800":0,"1454479200":0,"1454565600":0,"1454652000":0,"1454738400":0,"1454824800":0,"1454911200":0,"1454997600":0,"1455084000":0,"1455170400":0,"1455256800":0,"1455343200":0,"1455429600":0,"1455516000":0,"1455602400":0,"1455688800":0,"1455775200":0,"1455861600":0,"1455948000":0,"1456034400":0,"1456120800":0,"1456207200":0,"1456293600":0,"1456380000":0,"1456466400":0,"1456552800":0,"1456639200":0,"1456725600":0,"1456812000":0,"1456898400":0,"1456984800":0,"1457071200":0,"1457157600":0,"1457244000":0,"1457330400":0,"1457416800":0,"1457503200":0,"1457589600":0,"1457676000":0,"1457762400":0,"1457848800":0,"1457931600":0,"1458018000":0,"1458104400":0,"1458190800":0,"1458277200":0,"1458363600":0,"1458450000":0,"1458536400":0,"1458622800":0,"1458709200":0,"1458795600":0,"1458882000":0,"1458968400":0,"1459054800":0,"1459141200":0,"1459227600":0,"1459314000":0,"1459400400":0,"1459486800":0,"1459573200":0,"1459659600":0,"1459746000":0,"1459832400":0,"1459918800":0,"1460005200":0,"1460091600":0,"1460178000":0,"1460264400":0,"1460350800":0,"1460437200":0,"1460523600":0,"1460610000":0,"1460696400":0,"1460782800":0,"1460869200":0,"1460955600":0,"1461042000":0,"1461128400":0,"1461214800":0,"1461301200":0,"1461387600":0,"1461474000":0,"1461560400":0,"1461646800":0,"1461733200":0,"1461819600":0,"1461906000":0,"1461992400":0,"1462078800":0,"1462165200":0,"1462251600":0,"1462338000":0,"1462424400":0,"1462510800":0,"1462597200":0,"1462683600":0,"1462770000":0,"1462856400":0,"1462942800":0,"1463029200":0,"1463115600":0,"1463202000":0,"1463288400":0,"1463374800":0,"1463461200":0,"1463547600":0,"1463634000":0,"1463720400":0,"1463806800":0,"1463893200":0,"1463979600":0,"1464066000":0,"1464152400":0,"1464238800":0,"1464325200":0,"1464411600":0,"1464498000":0,"1464584400":0,"1464670800":0,"1464757200":0,"1464843600":0,"1464930000":0,"1465016400":0,"1465102800":0,"1465189200":0,"1465275600":0,"1465362000":0,"1465448400":0,"1465534800":0,"1465621200":0,"1465707600":0,"1465794000":0,"1465880400":0,"1465966800":0,"1466053200":0,"1466139600":0,"1466226000":0,"1466312400":0,"1466398800":0,"1466485200":0,"1466571600":0,"1466658000":0,"1466744400":0,"1466830800":0,"1466917200":0,"1467003600":0,"1467090000":0,"1467176400":0,"1467262800":0,"1467349200":0,"1467435600":0,"1467522000":0,"1467608400":0,"1467694800":0,"1467781200":0,"1467867600":0,"1467954000":0,"1468040400":0,"1468126800":0,"1468213200":0,"1468299600":0,"1468386000":0,"1468472400":0,"1468558800":0,"1468645200":0,"1468731600":0,"1468818000":0,"1468904400":0,"1468990800":0,"1469077200":0,"1469163600":17,"1469250000":0,"1469336400":0,"1469422800":3,"1469509200":14,"1469595600":54,"1469682000":0,"1469768400":4,"1469854800":1,"1469941200":0,"1470027600":0,"1470114000":0,"1470200400":1,"1470286800":0,"1470373200":1,"1470459600":0,"1470546000":0,"1470632400":0,"1470718800":0,"1470805200":0,"1470891600":2},
  '/u/root/calendar_activities'
);
```


After:
![Screen_Shot_2016-08-11_at_3.56.36_PM](/uploads/9325cdb8c0271075abee2a838c1a0787/Screen_Shot_2016-08-11_at_3.56.36_PM.png)

```
new Calendar(
  {"1469163600":17,"1469422800":3,"1469509200":14,"1469595600":54,"1469768400":4,"1469854800":1,"1470200400":1,"1470373200":1,"1470891600":2},
  '/u/root/calendar_activities'
);
```
## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- Tests
  - [x] All builds are passing
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !5784

Capitalize mentioned issue timeline notes

## What does this MR do?
Renames `mentioned in` to `Mentioned in` for issue timeline notes

## Are there points in the code the reviewer needs to double check?
Shouldn't be any :smile: 

## Why was this MR needed?
Resolves existing UI inconsistency as all the other issue timeline notes have their first letter capitalized.

## What are the relevant issue numbers?
Closes #21416 

## Screenshots (if relevant)
Before:
![Screen_Shot_2016-08-25_at_10.52.47_AM](/uploads/61de0a7d65fd739a6e565f6e63d2f52d/Screen_Shot_2016-08-25_at_10.52.47_AM.png)

After:
![Screen_Shot_2016-08-25_at_10.52.05_AM](/uploads/f67f353c285453306d6b80578b11e587/Screen_Shot_2016-08-25_at_10.52.05_AM.png)

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- Tests
  - [x] All builds are passing
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !6028

Add hover color to emoji icon

## What does this MR do?
Adds hover color to emoji icon in discussions

## Are there points in the code the reviewer needs to double check?
Shouldn't be

## Why was this MR needed?
Keep consistency of color highlighting to indicate action icon

## What are the relevant issue numbers?
Closes #20629 

## Screenshots (if relevant)
Before:
![Gcy0V4Cjp9](/uploads/96a7a683fe2d526b74a05d7cc91c9fa0/Gcy0V4Cjp9.gif)
After:
![TAmusA6o1z](/uploads/1baf20390d2f1442b5fae84ae42914ce/TAmusA6o1z.gif)

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- Tests
  - [x] All builds are passing
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !5673

Fix external issue tracker "Issues" link leading to 404s

## What does this MR do?

This MR fixes the redirection to the wrong URL when using an external issue tracker, such as JIRA or Redmine.  a70431f874 modified the behavior to link to the external issue tracker
issues URL instead of the project path URL. This restores the previous behavior.

## Why was this MR needed?

The issues URL often has `:id` associated with it for linking mentioned issues.
For external issue trackers, the project page is the intended target.

## What are the relevant issue numbers?

Closes #21252

Related to #21402

See merge request !6006