changes in tunnel.py to falg the dead peers
changes in db.py to remove old peers when necessary

You can flag peers ( in vifibnet ) so that they are chosen last when looking for a peer to connect to.

Conflicts:
	vifibnet.py

Conflicts:
	TODO
	plib.py

in upnpigd : now open a port in tcp too

in plib.py : the address attributed to the server iface was XXXXX/len(network) wich resulted in XXXXXX/48 while it should be XXXXXX/len(subnet of a single machine)
in vifibnet.py : the -l option was broken
in tunnel.py : routes count is now stored on each connection object and not in the tunnelManager object

Tunnel manager can now see how many routes goes to each tunnel. This is still not very acurate since I don't filter on the size oof the subnet.

Conflicts:
	TODO