The preview.blend now shows raytracing/transparency, and also turns on and off
the fake shadow based on the 'shadbuf' setting.
Also included an updated preview.blend file to accomodate this.
- Improved lighting and background (also turned off shadows, unnecessary and
a potential slowdown in generating the preview)
- UV unwrapped the sphere and monkey models, so you can actually see something
useful when a texture is mapped to UV
- Added a 'hair' preview option (reused sphere icon will be eventually
forthcoming)