Test Architecture Tweak

As I was starting to write tests for sync-fork, wanted to try and simplify the test architecture a little bit.
Tests now update the remote with a second repository instead of using local and resetting.
This was just easier for me to think about and more closely mirrors reality.

@kevgo what do you think?

Note: I used git-extract to pull this off my sync-fork branch.
The branch name shouldn't be necessary here, since we set it to the feature branch above. I again don't feel strongly about this, if you have a good reason why we should always provide the branch name here, then we can do that.