Rugged/Grit push conversion

As the title says. It has taken we quite a while to get the Rugged commands right, so I'm going to open a PR just for this. I plan to work on the pull next, and I anticipate it will take as long.

This includes an improvement to waiting during the full_sync integration test,
and some Rubocop style updates in the Repository related files.

Test all pass locally, and if Travis is happy then this should be ready to merge.

Now on to the pull method. :)