Add sun position automatic uniform.
Start adding sun rendering.
Merge branch 'master' into sun

Conflicts:
	Source/Scene/SceneTransitioner.js
Frustum cull the sun.
Add fragment shader for pretty lame looking sun.
Update sun fragment shader.
Draw sun after the sky atmosphere.
Merge branch 'master' into sun
Merge branch 'master' into sun
Re-add sun bloom without post-processing framework.
Remove unused code and minor tweaks.
Remove hacked bloom and add it to the scene as a post process when the sun is visible.
Rename downScale -> downSample.
Start scissoring out the sun by enabling the scissor test on the down sampled passes.
Fix down sample scissor rectangle position and continue up sample scissor work.
Finish adding scissor tests and clear additional framebuffers.
Try to blend scissor bloom with the rest of the scen a little better.
Correctly size the sun.
Make solar radius a math and shader constant.
Clean-up Scene and fix error in ShaderProgram.