logoff on suspend
Gajim should log off before the system is suspended, which is a common event in a mobile environment. I've used this feature with Psi, and it was very helpful. Right now i get these annoying popups every time turn the laptop back on. This is in progress in #859 (closed), but logoff is helpful for people subscribed to my presence. The problem is portability here, it's possible in Windows, but have no idea how's it with other OSes.