Add the git-overwritten plugin from mislav
Change my git bisect aliases since this is what I think they are all the time anyway
Update git log aliases

* Change the date format for easier scanning
* Truncate long author information > 25 characters
* Change colors to be simpler
* Truncate long commit subjects > 120 characters
* Right justify branch names
* Show commit body if there is one
Add git log aliases which do not include the commit body