Add Telepathy related formulas (new formulas)

This branch adds the formula for  [Telepathy](http://telepathy.freedesktop.org/wiki/) and some [components](http://telepathy.freedesktop.org/wiki/Components/) that make it useful.

It adds these formulas: 

* telepathy-glib: main library
* telepathy-gabble: xmpp
* libnice: gabble dependency
* telepathy-idle: irc
* telepathy-mission-control: an Account Manager and Channel Dispatcher implementation, which stores accounts and coordinates the launching of connection managers and clients.
Python is only required at buildtime?