Component Ids (#1501) * Component id + prune those for refresh as well * Serialize id properly * Add unit tests for component id serialization / deserialization - make sure references to Components with Property are properly restored to the correct components by id * Update GameObjectInspector to use Component.Id to determine already seen components. This makes it rebuild properly for multiple components of the same type * Serialize as Id not __id so also picked up by MakeGameObjectsUnique * Scene unique component ids - update serialization test accordingly * Phase out storing GO guid and component type * MakeGameObjectsUnique -> MakeIdGuidsUnique (make old method Obsolete and redirect to MakeIdGuidsUnique) * Unit test for clone with references * When adding component or game object to Directory - check is there a component or game object with that id already, if so, force change it to a new one and spit a warning out. No component or game object should ever be able to share the same guid anyway but this makes sure * Add test for loading old reference model type from prefab / json * Test both old and new formats * Let's not make this elseif - always check both