Fix #636 - Improve message when asking for vnc informations
Fix #628 - Check if vm is running before get network stats
Fix bad description in chat for appliance
Fix an issue with network stat, as Alias tag do'esnt exist on xen domU, replaced by target in this case.
Merge branch 'agent-chat-improvements' of https://github.com/CyrilPeponnet/Archipel into pr-652