Reauthenticate novaclient to ensure token is still valid.
Closes-Bug: 1335854

Add availability zone for service instance VM launch
Closes-Bug: 1341455

Update log messages
Add additional check for service vm/netns already created

Change-Id: I7a6d094c8eb0a86a7c91f3f5733ce6c1227f8165
Merge "Reauthenticate novaclient to ensure token is still valid. Closes-Bug: 1335854"