cxmanage: Use comma-separated addresses for hostname
cxmanage: Use comma-separated addresses for hostname

I.E.
cxmanage power on 192.168.100.100,192.168.100.101

This should make it a little easier to keep track of the
positional arguments. Space-separated addresses stopped working
at some point anyway.

SLS-Dev/cxmanage,Cynerva/cxmanage,SLS-Dev/cxmanage,SilverLiningSystems/cxmanage-test,SilverLiningSystems/cxmanage-test2,SilverLiningSystems/cxmanage-test2,SilverLiningSystems/cxmanage-test,Cynerva/cxmanage