Load model from prefab instance

A new ACE has been added, Load model from prefab instance.

This is used for only instance models of the same object type (instance property checked). It allows for other instance models to be loaded from a previously loaded instance based on UID. The previously loaded instance must be of the same object type/name and the prefab instance must have completed loading.

This make it easier and more efficient to load models during runtime and create new instance models with low impact on GPU memory, since the models based on the prefabs will use the prefabs instance's texture memory. Note that since this is the case, if the original prefab model is destroyed, the other instances based on it will be destroyed also. So, instead move the prefab instance offscreen or not visible, etc.

Thanks to pixelmetal for the commission for this feature.