Merge pull request #815 from alphagov/rename-unprocessable-entity

Rename unprocessable_entity to unprocessable_content

Author: DavidBiddle

app/controllers/application_controller.rb

@@ -65,6 +65,6 @@ def missing_parameter(exception)
   end
 
   def invalid_record(resource)
-    render json: resource.record.errors, status: :unprocessable_entity
+    render json: resource.record.errors, status: :unprocessable_content
   end
 end