Refactor update creation api

This merge request does the following:

• Raise DRF errors rather than returning response to take advantage of the DRF exception handling mechanism
• Create serialisers for PUT request to simplify the code
• Improve validation checks in several places
• Fixes several issues in DRF infrastructure uses
• Fixes JSON fields handling
• Remove routes that do no fully qualify objects
• Implement a custom DRF exception handler that will allow to log errors
• Improve testing
• Improve permission management

beat/web/databases/tests.py

@@ -131,6 +131,7 @@ class DatabaseCreationAPI(DatabaseAPIBase):
         databases = Database.objects.all()
         self.assertEqual(databases.count(), 1)
         databases.delete()
+        dataformat.delete()
 
 
 class DatabaseRetrievalAPI(DatabaseAPIBase):