webremote: Add hostname to mdns service name
webremote: Add hostname to mdns service name

On networks with multiple mex instances running the collision service
rename stuff needed to be more readable so that people can work out
which instance is theirs. Instead of "Mex webremote N" it's now
"Mex webremote on HOST N".

media-explorer/media-explorer,media-explorer/media-explorer,media-explorer/media-explorer,media-explorer/media-explorer