Update git-cola to 3.9
- The startup dialog now detects when Recent and Favorite repositories no longer exist on disk, and offers to remove these entries when selected.
- The startup dialog now includes a simpler and more condensed folder view that can be used for selecting Favorites and Recent repositories.
- The "Commit" menu now includes an "Undo Last Commit" action.
- The "Reset" menu was revamped to expose all of Git's reset modes alongside a new "Restore Worktree" action that updates the worktree using "git read-tree".
- Updated translations for Polish, Japanese and Brazilian.
- In packaging, the --use-env-python option for setup.py is now Python3 compatible.
- Browse git-cola repo using the GUI, see the diff changes.
- Perform git-add and git commit from GUI.
Reviewers: Triage Team, JoshStrobl
Reviewed By: Triage Team, JoshStrobl
Differential Revision: https://dev.getsol.us/D10591