Merge branch 'sup-heliotrope/develop' into maildir-sync
Merge branch 'sup-heliotrope/develop' into maildir-sync
Merge branch 'sup-heliotrope/develop' into maildir-sync
labels got lost
Merge branch 'sup-heliotrope/develop' into maildir-sync

Conflicts:
	lib/sup/poll.rb
Merge branch 'sup-heliotrope/develop' into maildir-sync
Merge branch 'sup-heliotrope/develop' into maildir-sync
Merge branch 'sup-heliotrope/develop' into maildir-sync
Merge branch 'sup-heliotrope/develop' into maildir-sync
Merge branch 'sup-heliotrope/develop' into maildir-sync
Synchronize maildir syncback (#137)

It is possible for maildir sync back to occur during polling. To prevent this,
syncback now locks the source before writing back labels.

poll_lock is now a monitor instead of a mutex, so reentrant locking is
possible. Sources can be locked directly using Source#try_lock, Source#unlock
and Source#synchronize.

Moved some syncback logic from Message to Location. The configuration check
for syncback is now also checked there, so we can add source-specific syncback
per source (see #141).
Bump rmail dependency to fixed rmail-sup
Merge pull request #143 from sup-heliotrope/change-rmail-dep

Bump rmail dependency to fixed rmail-sup
Don't try to modify non-existent message on forward of attachment only
Merge pull request #145 from gauteh/dont_save_forwarded_with_no_message

maildir-syncback: forward message (with only attachment) fails
Merge pull request #137 from ericweikl/fix-137-poll

Maildir-syncback: Synchronize with poll_lock (possibly in a non-blocking way/or a separate thread) in all operations that write a new message or changes a message
Merge branch 'sup-heliotrope/develop' into maildir-sync
remove call to Redwood::check_library_version_against

It was removed from sup in Pull Request #51 and nobody noticed, I guess.
Individual sync_back configuration option

It's now possible to (de)activate Maildir sync back per Maildir source, using
the sync_back source configuration flag. For backwards compatibility with the
previous implementation, the global :sync_back_to_maildir still exists and
must be set to allow sync back. Additionally, sync back is _active_ by
default per source, i.e. unless sync_back is explicitly set to false, sync
back will occur.

Fixes #141
fix_encode body before regexping to check for top_posting?