OmniLight3D:
* Fixed lack of precision in cube map mode by scaling the projection's
znear.
* Fixed aliasing issues by making the paraboloids use two square regions instead of two half
squares.
* Fixed shadowmap atlas bleeding by adding padding.
* Fixed sihadow blur's inconsistent radius and unclamped sampling.
SpotLight3D:
* Fixed lack of precision by scaling the projection's znear.
* Fixed normal biasing.
Both:
* Tweaked biasing to make sure it works out of the box in most situations.
-Used a more consistent set of keywords for the shader
-Remove all harcoded entry points
-Re-wrote the GLSL shader parser, new system is more flexible. Allows any entry point organization.
-Entry point for sky shaders is now sky().
-Entry point for particle shaders is now process().
-All shadow rendering is done with raster now (no compute)
-All shadow rendering is done by rendering directly to the shadow atlas
-Improved how buffer clearing is done to optimize the above.
-Ability to set shadows as 16 bits.
