Vega Strike Code

milky_way.xml improvements, tying terrestrial planets with earth technique
Covers a great chunk of all planets. Won't tie gas giants yet...

Nicer Redemption/Bernards Star/jacobs
(showing how earth techniques also work for desert planets)

Technique improvements:
* sRGB awareness for earth technique
* sRGB awareness documentation in DTD
* gas giants technique prototype (not used yet)
* Proper multi-pass lighting (may be a tad heavy on the GPU though)
* Better sequencing and z-sort settings
* default technique in all shader profiles
(some meshes explicitly reference a "default" technique)

Tons of improvements to planet shaders, including:
* Proper multilight handling (needs further changes to techniques which will be committed shortly)
* Improved performance and looks
* Improved compatibility (lets hope... at least that's the intention).
Compatibility still has a long way to go though.
* Used include directives to factor out common sections into include files
- uniforms
- standard library of functions
- configuration defines
* sRGB support (needs further changes to techniques which will be committed shortly)
* Initial version of gas giants - a bit slow and glitchy, but a start

Also ignore *.pp in programs/planet

Make programs folder ignore preprocessed shaders (*.pp)

Useful script to process include directives within shaders off-line (ie: for inspection)

galaxy.xml (milky_way.xml in VS datasets) improvements to allow technique, unitname and parameter overrides in planets of random starsystems.
Will soon commit changes to milky_way.xml using this new capability.

Bugfix: multipass lighting techniques weren't working right.
This hopes to fix it.

sRGB framebuffer extensions support