Changed Branches and Tags tabs to dropdowns
Added commmit log info to commit detail page
Added a convenience method to get commits
Updated context
Added markdown processor to commit messages
Got rid of BranchDetail and TagDetail since we have dropdowns now
Installed guardian
Setup authentication stuff to help with testing
Updated Repository admin to GuardianAdmin
Added a permission to view repos to Repository
Did a bit of refactoring, and added access control to repository views
Added fixtures to setup some users and repos at startup when testing
Merge branch 'feature/guardian' into develop
Added a couple of tests to verify permissions
Catch errors when bad refs are used
Now storing current_branch with user's session

Helps keep track of which branch they're looking at
Fixed a silly mistake in tests
Got sessions working and changed the way we refer to refs

Instead of just the branch or tag name, use the whole "refs/heads/..."
(or whatever) path. It makes it WAY less confusing than trying to
figure out whether something is a branch or a tag. Especially when
someone creates a repo with branches and tags by the same name.
Merge branch 'feature/branch-sessions' into develop
Displays trees!

Doesn't pass paths around right, though. Either need a way to
concatenate paths, or need to rewrite the get_tree function to return
full paths, not just file names.