Added '?' key command to display control keys in sip_publish_presence

darcs-hash:20090216125652-1e3d8-f96a1021c3f7fdf709ab886a2278137acc6bc81d
Refactored ringtone start slightly in session.py

darcs-hash:20090216135655-58103-2d57ef2190cd5aac3ce087370d6831110d1e8d08