- server reconnection
 - vm registering
 - real TTL
 - less contention
 - super cool fixes
 - blah blah ...

Signed-off-by: Thibault VINCENT <thibault.vincent@smartjog.com>

 - list_vm now does tag filtering and vm name filtering
 - start and stop vm have name filtering 
 - stop_vm have now an optional parameter to force poweroff