More Player Models

- should fix crash with fire/ice mod
- mod on server and not on client should work now
- skin loading fixes
- hat layer not loading fix
- new config option to allow for fully invisible skins
- fix where back item wasnt showing<br />- small scaling fix<br />- /mpm name command fix

- camera improvements

- entity animation offset fixes
- entity url skin fixes
- sleeping head rotation fixes
- less head spazzing in camera mode
- gui preview rotation fix