NEW in 0.21.4:
=============
 - Cache avatar pixbuf in EmpathyChatView to avoid having a new pixbuf in memory
   for each message a contact sends
 - Generate ChangeLog from svn commits. Copy generator from epiphany.
 - Correctly store/restore presence when NM state changes.
 - Split EmpathyContactFactory to have one EmpathyTpContactFactory per account.
 - When NM is in sleeping (=disabled) state, do just like if it was connected.
   Add a gconf key to disable NM support completely.