title: Git on the road - push error '[remote rejected] master -> master (branch is currently checked out)'
body: <p>Let say I'm on the road with a friend, we are offline from the bare git repository.
  I have a working copy (with .git folder) and my friend want to help me out so he clone my git repository from my working copy and work on its own and of course both copy are checkout so basically I can not commit and he can not push until one of us make a branch. Is there a better way to do this? is there a way to not have our local master checkout? I guess I can always create a bare git locally and both of us can point to it but that seem a bit over killing.
  The goal is for him to merge easily his change to mine and then when I'm online I will commit all of that. </p>