arguments as xml file for wsmancli invoke

Hi,

I modified invoke method to pass xml file instead of single parameters to wsman command. I found that this is the only way to pass multiple parameters with the same key, eg. VDPropNameArray and VDPropValueArray pairs or PDArray. With this modification I can pass dict with key PDArray and value as list: ['Disk.Bay.12:Enclosure.Internal.0-1:RAID.Integrated.1-1', 'Disk.Bay.13:Enclosure.Internal.0-1:RAID.Integrated.1-1']
I hope you'll find it useful.

Kamil