relevant fixes to make cloudroast tests pass

 - removed image_meta_property default value in function def
 - add behaviors to poll image status
 - add new config items
 - corrected client to proper responses/requests against api
 - edited model serialization/deserialization to conform to real json
   model

Change-Id: I5992df42cc3513aeedf3576b6884e357ac088622
Merge "relevant fixes to make cloudroast tests pass"