Lots of model changes

Netwrapper now handles entities differently to compensate for clients
not always having the entity when one is sent. Moved models into
models/drmatt/tardis/exterior and /models/drmatt/tardis/2012interior.
Materials have been moved similarly. The interior can no longer be seen
if the tardis is pointing at the sky, should also slightly increase
framerate. All materials are now packed with the addon, legacy tardis no
longer required for exterior materials. Updated materials with Benjas
latest. Added test texture for door, marking the beginning of interior
texturing.