git-prune-remote-branch

Delete all remote branches which merged into master or develop.

$ git clone git://github.com/kyanny/git-prune-remote-branch.git
$ export PATH=/path/to/git-prune-remote-branch:$PATH
$ cd $GIT_DIR
$ git-prune-remote-branch --help
$ git-prune-remote-branch --noop

http://kyanny.mit-license.org/