logging.NullHandler has been present since Python 3.1, we don't need to
handle its absence.

* url_helper: drop six

* url_helper: sort imports

* log: drop six

* log: sort imports

* handlers/__init__: drop six

* handlers/__init__: sort imports

* user_data: drop six

* user_data: sort imports

* sources/__init__: drop six

* sources/__init__: sort imports

* DataSourceOVF: drop six

* DataSourceOVF: sort imports

* sources/helpers/openstack: drop six

* sources/helpers/openstack: sort imports

* mergers/m_str: drop six

This also allowed simplification of the logic, as we will never
encounter a non-string text type.

* type_utils: drop six

* mergers/m_dict: drop six

* mergers/m_list: drop six

* cmd/query: drop six

* mergers/__init__: drop six

* net/cmdline: drop six

* reporting/handlers: drop six

* reporting/handlers: sort imports

Allow users to provide '## template: jinja' as the first line or their
#cloud-config or custom script user-data parts. When this header exists,
the cloud-config or script will be rendered as a jinja template.

All instance metadata keys and values present in
/run/cloud-init/instance-data.json will be available as jinja variables
for the template. This means any cloud-config module or script can
reference any standardized instance data in templates and scripts.

Additionally, any standardized instance-data.json keys scoped below a
'<v#>' key will be promoted as a top-level key for ease of reference in
templates. This means that '{{ local_hostname }}' is the same as using the
latest '{{ v#.local_hostname }}'.

Since instance-data is written to /run/cloud-init/instance-data.json, make
sure it is persisted across reboots when the cached datasource opject is
reloaded.

LP: #1791781

Currently the python logging module will default to a local time which may
contain an TZ offset in the values it produces, but the logged time format
does not contain the offset. Switching to UTC time for logging produces
consistent values in the cloud-init.log file and avoids issues when the
timezone is changed during boot.

LP: #1713158

This has been a recurring ask and we had initially just made the change to
the cloud-init 2.0 codebase.  As the current thinking is we'll just
continue to enhance the current codebase, its desirable to relicense to
match what we'd intended as part of the 2.0 plan here.

- put a brief description of license in LICENSE file
- put full license versions in LICENSE-GPLv3 and LICENSE-Apache2.0
- simplify the per-file header to reference LICENSE
- tox: ignore H102 (Apache License Header check)

Add license header to files that ship.
Reformat headers, make sure everything has vi: at end of file.

Non-shipping files do not need the copyright header,
but at the moment tests/ have it.

to be behind trunk.

`tox -e py27` passes full test suite.  Now to work on replacing mocker.

Exeptions were being swallowed completely and no way to even see them
other than log.

make pep8 now is silent on precise's pep8 ( 0.6.1-2ubuntu2).

iterable which performs the same, but can handle iterator
types beyond those three.