holy diff batman!

[Jingle] Volume levels are saved, audio UI shows up even if there are errors, until the session ends

Import socket in jingle_rtp, fixes typo in 'stun_server', connect changed signal of stun_server_entry Fixes #5502

Renamed a few methods, refactor on_*_button_toggled, use getattr/setattr instead of eval/self.__dict__

There is still room for improvement, but it should be better.