Replaced hard coded states with enums

* Changed admin actions tests to use NovaServerStatusTypes
  to verify state transitions

Change-Id: Ia2fa9a6242028b1982d547160bef424fe0651eb3
Corrects parameter sent to instance action validation

* Now passes project id instead of tenant id for
  instance action validation

Change-Id: Ideedfa6ae3a86f76cd39d59bd40dadf25f1e37d2
Merge "Replaced hard coded states with enums"