Master needs a python git package for gitfs

[edunham]

https://docs.saltstack.com/en/2015.5/topics/tutorials/gitfs.html says it's the preferred method.

It looks like we're not managing any of the salt-master config within salt itself, so this dependency is the only change for #264

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This change is

[aneeshusa]

Do we still need to install git explicitly, or will it get pulled in as a dependency or fulfilled by python-pygit2? I only added it to support the existing workflow of manually pulling, so let's remove it if it's not needed.

Also, I think it also makes sense to move this state to a new folder + file salt/master.sls instead, to make its purpose more clear, and get rid of the git folder.

[aneeshusa]

Actually, the Salt docs note that python-pygit2 isn't available in the Ubuntu Trusty repos, and Travis corroborates this. It does seem to be available from 15.10 onwards, though.

[edunham]

Might as well just use GitPython, then.

Ubuntu 14.04 LTS and Debian Wheezy (7.x) also have a compatible version packaged:
$ sudo apt-get install python-git

Amended commit, and rebased onto current master branch to pull in the workaround for the Travis intermittents.

[edunham]

Closing because I'm adding some other saltmaster-specific states and renaming the git directory for another PR, and I'll stick this change into there