Check if VM status is not "Host Not Responding" before getting IPs

Running the Read-SCGuestInfo cmdlet to gather VM IP addresses causes a WinRM Error 500 to be generated when the VM Status is "Host Not Responding". This status occurs when a VM and Host are not communicating over WinRM / HTTPS preventing the VM heartbeat from being exchanged.
To Do: Add event support for a change in VM status so we can kick off an EMS refresh.
Merge pull request #294 from bronaghs/scvmm_host_not_responding_error

Check if VM status is not "Host Not Responding" before getting IPs