Rejigged serialization handling to allow the creation of multiple EntitySystemLibraries, with type handlers customised for different situations (e.g. networking)
Removed EntityRefTypeHandler network ref hack, split out into separate type handler
Fixed a bug with the EntitySerializer's deserializeOnto - was removing all components
Removed LoadEntities step from client loading process - was wiping initially replicated entities
Cleaned up the network classes, moving more server/client specific handling into the Server/ClientPlayer classes