Adds `git_left yolo`, minor improvements

• Adds git_left yolo which will enable you to throw your hands in the air and remove all git repositories at once
• Monkey-patch the ruby-git gem to improve branch fetching. It should be fast now
• Re-add end-of-session reporting. It was tragically lost during a refactor

Minor updates

• Monkey-patch ruby-git gem to increase performance when fetching large number of branches

Minor updates

• Add ability to prune remote branches when starting session
• Expanded on branch reporting functionality
• Minor refactoring

Minor updates

• Sped up Git::Branch retrieval
• Protected against unforeseen errors