Merge branch 'rr/push-head' into maint

* rr/push-head: push: make push.default = current use resolved HEAD push: fail early with detached HEAD and current push: factor out the detached HEAD error message

Junio C Hamano committed Jun 27, 2013 at 14:38 UTC 6be17ec5828386c3ae17af26fac66f65f1c817ec

No changes.