SQL performance in the profile, preparations to twitter integration

I found out that the forced index in the profile was good for profiles with many entries - but bad for profiles with only a few items. I reverted that change until I have a solution for both, small and huge profiles.

Secondly there are some lines of code for the upcoming twitter sync. It only ensures that you will see "Twitter" in the contact list and that shared items from Twitter will have the twitter name.