Master needs python-git for gitfs

https://docs.saltstack.com/en/2015.5/topics/tutorials/gitfs.html says it's the preferred method. Working on #264.
servo · edunham · Mar 23, 2016 · Mar 24, 2016 · 639dae9dfb21e5fe30e14c176893db161cbfb388
commit 639dae9dfb21e5fe30e14c176893db161cbfb388
diff --git a/git/init.sls b/git/init.sls
@@ -2,4 +2,4 @@
 git:
   pkg.installed:
     - pkgs:
-      - git
+      - python-git