Addressees in the KDE PIM Features Branch

Thanks to Christian we have a bunch of clean-ups in the way KMail's addressee and recipient editors work. This new code will probably be fast-tracked[1] into the 3.5 branch, but for now we have it only in the features branch for testing. So, please do test.

Feedback to kmail-devel@kde.org please. Not all of our new contributors are reading my blog.

In particular, this patch addresses the following bug reports (at least):

Bug 98691: tab completion last name / nickname
Bug 76739: Partial string search for contacts in address fields
Bug 77342: include nicknames in address lookup
Bug 109798: apply distinct on address in dropdown for autocomplete
Bug 107945: wrong/strange autocomplete in composer addressfield

[1] I mean that the KMail core developers already have reviewed the code and seem to like it, and this is really bug fixing and not a set of new features.