Contact performance fixes

began as work dealing with ContactAdapter freezing up with too many requery/refresh calls due to a variety of things. ended up becoming much more work than it should have been, but mostly all good.

1) ContactAdapter now overrides onContentChanged and only reloads itself at a certain interval window, batching any updates

2) Contact cursor does not include avatar byte[]; that is now a remote method call on IContactListManager

3) cleaned up roster loading at login; just generally works better

4) much improved presence handling with queing, executor use, smarter avatar image loading

5) Fixes for account registration/create which was broken at some point