git

gistfile1.txt

git remote prune origin - to remove a deleted remote branch.
git rebase -i - interactive rebase with options to pick, squash, discard and reorder commits.
git update-index --assume-unchanged

Undoing a merge:

$ git pull $REMOTE $BRANCH
# uh oh, that wasn't right
$ git reset --hard ORIG_HEAD
# all is right with the world


git push -u remote_name branch_name - to make a local branch_name as a remote branch