Added some expermental support for remote repos in PRs,
also fixed some issues that @justinabrahms brought up.
Checked against current PR, it helps if you change directories before messing with git
Make sure we are in the correct directory for all git operations
Merge @scottjab's support for remote repos.

Slightly reworked the original to push more state into classes rather
than the main method.

Fixes #12, #11, #7