Improved error handling in ts3-module.

 - Pass all callback errors as exceptions.
 - Made sure that all asynchronous methods have a callback-argument.
 - Made sure that no callbacks were left uncalled.
 - Detect errors as low level as possible and notify state machine when necessary.
 - Fixed some infinite recursion loops.
 - Pass logs received from asyncore to WOT's logging system.
Fixed TS user's nickname change not detected.