Use the warnings module to display the git version message.

This allows us to ignore the error:

```python
    warnings.filterwarnings(
        'ignore',
        category=UserWarning,
        module='salt.version'
    )
```
Or, make it raise an exception:

```python
    warnings.filterwarnings(
        'error',
        category=UserWarning,
        module='salt.version'
    )
```
Remove the warnings filter from `salt.version`.
moving to new upstream version 0.12.0
Defer imports to a later stage so Jinja2 does not become a build dependency. Fixes #3293.
Merge pull request #3294 from s0undt3ch/issues/3293

Defer imports to a later stage so Jinja2 does not become a build dependency. Fixes #3293.
Jinja2 is no longer a build dependency. Fixes #3293.
Merge pull request #3295 from s0undt3ch/issues/3293

Jinja2 is no longer a build dependency. Fixes #3293.
Use `salt.utils.fopen` within `salt.utils`? Nope! How did it even work?!
Fixes saltstack/salt/#3273
Merge pull request #3296 from torhve/loopinterval

Fixes saltstack/salt/#3273
Added support for adding postgres user to group in state.
Added state for managing postgres groups
Revert the changes needed to fix #3293.
Merge branch 'develop' of github.com:saltstack/salt into develop
add note about fetching tags
Don't unsubscribe, there is no need to and it leaves zeromq

in the wrong state for a few moments and breaks the client
merge differences and mention fetching tags
Merge pull request #3299 from seanchannel/develop

update "hacking" files to match
Default "refresh" to False in pkg.upgrade (apt)

This fixes #3300. Also made pep8 fixes. python-mode FTW!
Fix #3300

Per @thatch45, pkg.upgrade will still default to refresh=True, but
list_upgrades will gain a "refresh" argument (which will also default to
true). This behavior will become the new default when #3210 is
implemented.