Revert "Make nicer pull request merge messages"
Revert "Make nicer pull request merge messages"

This reverts commit 1078fb08851442bcd7750c3d5015dc1fe7e4d927 (and thus
pull #5623). It has various issues:

- Pull request names get cut off at ", see e.g. a026a56

- Merge script no longer copes with pulls that have a milestone
  attached, due to a duplicate 'title' in JSON that is not handled by the
  ad-hoc parsing.

wastholm/bitcoin,wastholm/bitcoin,wastholm/bitcoin,wastholm/bitcoin,wastholm/bitcoin,wastholm/bitcoin