Help! Offlineimap has become very unstable

[sebastian at sspaeth.de]

It has been reported by John that recent offlineimap is causing him lots
of instability. The reason is that APPENDED messages will not get the
correct messeage UID, as we wither don't get the right APPENDUID response
or fail to parse it properly.

There have been two changes in that code in recent times. They are commits

https://github.com/spaetz/offlineimap/commit/47390e03d6a07b2ab73b65b74b668b7ce0663f57
(removing checkpointing after each message if the server supports APPENDUID)

and commit
https://github.com/spaetz/offlineimap/commit/4d47f7bf3c7e0af56e0bc1f74c3afe6c762beb3e
(
I will revert both in the next branch now, to make sure we don't regress
badly here, and we'll need to reintroduce changes carefully, and using the
new test suite facilities.

The reverts cause slight merge conflicts and are now in 'next' as these
commits:

0e6b4ae Revert "Clean up and improve APPENDUID handling"
bc73c11 Revert "Don't CHECK imapserver after each APPEND"

I would be interested to hear, which -- if any -- of the changes causes
the instabilities and if someone would revert only one of the two patches,
reporting if it helps fix the instabilities.

That having said, both patches are now reverted in 'next'. John, may I ask
you to try if it works indeed better with current next? THanks, and sorry.

Sebastian