New git alias: git last

I made a new git alias I'm loving. Maybe you have something similar.

I've added this to my .gitconfig:

[alias]
    last = rev-parse --abbrev-ref @{-1}

This gets the name of the branch you had checked out prior to the current branch. It's like git checkout -, but you can use it all over, such as:

$ git merge `git last`