REST API validation implementation

* All json schemas are implemented
* Basic validation is done excepts plugin configs, cinder feature and scaling

Implements blueprint savanna-rest-api-1-0-validation

Change-Id: I7ff633a8764d17bf3ba49c2362e2dbbedefd61cd
Some logging added to cluster provisioning

Change-Id: I49d5da2c414c6c898412e838819e6678c28d4c2f
Merge "REST API validation implementation"
Merge "Some logging added to cluster provisioning"