Merge branch 'jn/revert-quit'

* jn/revert-quit:
  revert: remove --reset compatibility option
  revert: introduce --abort to cancel a failed cherry-pick
  revert: write REVERT_HEAD pseudoref during conflicted revert
  revert: improve error message for cherry-pick during cherry-pick
  revert: rearrange pick_revisions() for clarity
  revert: rename --reset option to --quit