Avatars+Gossip+Telepathy

Hi !

I have started implementing avatars for the gossip branch using
telepathy. I am also implementing the server-side group support. Both of
these use experimental (non-reviewed) branches of the gabble connection
managers, so unfortunately is relatively hard to try these out yet.

Avatars work already, but there are some issues which i want to raise
here:
 * Since we need some persistant storage of the avatar token (to
optimize bus transfers) what API should i use to store a contact's
avatar ID to disk and read it back on restart. I suspect it involves
xml, am I right? Any pointer is appreciated here.
 * This is a general problem in the Telepathy branch, every single
telepathy dbus call is synchronous. In the case of avatars it breaks
horribly since requesting an avatar is a direct IO operation over the
network. The whole branch need to be ported to async calls everywhere. I
can do this, but right now i prefer to concentrate on features. When i
finish avatars and server-side groups, i will start porting everything
to async calls.

As for the Server-side groups, i am going to start later today, i
already read the API. I still need to observe the existing code and find
the good spot to add the code for it.

I hope no-one else is doing this, or we might have an overlap here. If
it's the case please manifest yourselves !

See you !
Raf