Add git recent branch alias

[maxprehl]

https://twitter.com/tenderlove/status/1392957802163802112?s=20

Sorting git branches by "last activity" is much more helpful for me than by name. Here is an alias I use to list branches by activity:

git config --global alias.recent 'branch --sort=-committerdate --format="%(committerdate:relative)%09%(refname:short)"'