proxy65_manager idle objects spin unnecessarily

Bug description

I noticed gajim eats too much CPU on startup and realized idlequeue._process_events does about 20000-60000 calls to pollin() methods in proxy65_manager objects. I think it's because state machines in HostTester and ReceiverTester don't ever reach "finished" state and don't remove themselves from idle queue.

The attached patch fixes the problem for me - I assume the only task of HostTester and ReceiverTester is checking if connection is possible and disconnecting immediately.

Steps to reproduce

Try running with "gajim -m cProfile -o pstats gajim.py" and see calls to pollin(). With slower internet connection the bug is more visible.

Software versions

OS version: Ubuntu 9.10 x86_64 GTK version: 2.18.3 PyGTK version: 2.16