Reverted to old peer_monitor system.

This is due to the fact that maintaining a separate thread to listen
on DBus creates problems with GTK applications.
Fail silently when querying remote peers
Bugfix: Peer monitor did not get peer IP addresses
Merge branch 'develop' of https://github.com/ers-devs/ers into feature/ers-daemon

Conflicts:
	ers-local/ers/ers.py
	ers-local/ers/peer_monitor.py