Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Added troubleshooting to migration doc

@jacobvosmaer any thoughts?

See merge request !1482

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Include full path of source and target branch names in New Merge Request page

The previous title on the New Merge Request page would only show the group name. which could be confusing. Before, if you attempted to create a new merge request within the repo, it might look like this:

![image](https://gitlab.com/stanhu/gitlab-ce/uploads/d300d3a362406628ffc7c8f2b5cc6b5d/image.png)

Since they are in the same repo, this MR just simplifies this to the branches:

![image](https://gitlab.com/stanhu/gitlab-ce/uploads/5d7b3efc2399b37f84ccfd42bd5d6e8d/image.png)

However, if you create a MR from a forked project, you now see the full namespace:

![image](https://gitlab.com/stanhu/gitlab-ce/uploads/7998c3d19e90d405f4634202cc7181c5/image.png)





Closes #2875

See merge request !1477

Note the original location of a moved project when notifying users of the move

https://dev.gitlab.org/gitlab/gitlabhq/issues/2536

See merge request !1463

Take advantage of `Devise.sign_in_after_reset_password`

Since we've updated our Devise dependency, we can take
advantage of this new-ish configuration setting and avoid
our hackish workaround.

See merge request !1475