Merge branch 'ps/contrib-sweep' into jch

Remove bunch of stuff from contrib/ hierarchy.

I've reverted the thunderbird thing for now.

* ps/contrib-sweep:
  Revert "contrib: remove "thunderbird-patch-inline""
  contrib: remove some scripts in "stats" directory
  contrib: remove "git-new-workdir"
  contrib: remove "emacs" directory
  contrib: remove "git-resurrect.sh"
  contrib: remove "persistent-https" remote helper
  contrib: remove "mw-to-git"
  contrib: remove "hooks" directory
  contrib: remove "thunderbird-patch-inline"
  contrib: remove remote-helper stubs
  contrib: remove "examples" directory
  contrib: remove "remotes2config.sh"

Author: gitster