Improved Textures

Nine new patterns are added.
New warps are added, cylindrical, spherical, toroidal and planar mapping.
Texturing the difference: cutaway_textures.
Give the interior an other texture than the exterior: interior_texture.
Triangle texture interpolation, using a list of textures.
More natural light behavior for transparent objects with reflection: conserve_energy.
More natural reflection and a new finish reflection{} block. Adding fresnel reflection and manually controlled 'angle dependent' reflection.
Normal accuracy keyword for more control.
Keeping control over the bump height: normal no_bump_scale.
Filter now also works as filter in layered textures.
Transmit now works consistent inside as well as outside the 0 - 1 range.