IMMEDIATE:
 - Add Clone() method to SceneObject


Serialization
 - Proceeds as normal. Children serialized as ReflectablePtr array. Components also.
 - Potentially as a pre-processing step I break external references

Deserialization
 - Proceeds as normal except that handles are all resolved when ROOT deserialization ends (root because that ensures everything was constructed)
 - On local deserialization end (per SceneObject) I register all components and their old IDs in SceneObjectSerializationManager
   - Old ID is retrieved from GameObject RTTI
   - SceneObjectSerializationManager instance can be kept in SceneObjects rtti field.
 - When handles are resolved in root I perform "old->new" id mapping if one exists

Other
 - If external references need to be broken in serialized object that is done as a pre-processing step
 - If a clone of hierarchy needs to be serialized, that is also done as a pre-processing step
    - TODO - How will this be done?