Update Promenade Validate Design Status

Based on the API conventions [0], we will expect the status
to be 'Success' or 'Failure' instead of 'Valid' or 'Invalid'.

This patch set is meant to align with the UCP API conventions

[0] https://github.com/att-comdev/ucp-integration/blob/master/docs/source/api-conventions.rst

Change-Id: Iae45588ea0bceb4b9a4f7ecc9d15e66f7251a1ea

promenade/control/validatedesign.py

@@ -30,11 +30,11 @@ class ValidateDesignResource(base.BaseResource):
         if result['err_count'] == 0:
             message = "Promenade validations succeeded."
             status_code = falcon.HTTP_200
-            status = "Valid"
+            status = "Success"
         else:
             message = "Promenade validations failed."
             status_code = falcon.HTTP_400
-            status = "Invalid"
+            status = "Failure"
         resp.body = json.dumps({
             "kind": "Status",
             "apiVersion": "v1",