Adds many rendering related additions, tweaks, overhauls and fixes.

* Fixes that changing the video settings (and thus recompiling shaders) without relaunching the application was not working anymore
* Rewrites SSAO (now uses a hemispherical approach - variation of the approach used in Crysis)
* Adds a seprate 4x4 blur filter for SSAO (and an according pass)
* Changes that sunlight is applied via the deferred rendeirng path
* Adds that the chunk shader supports deferred and forward shading
* Changes that the reflected chunk scene is rendered using the forward path only
* Extends support for directional light sources
* Adds a main directional light for sunlight
* Moves shadow calculations from the combine pass to the light buffer pass
* Changes that dynamic shadows (plus cloud shadows) are only applied to the main directional light
* Adds that block sunlight gets encoded into the alpha channel of the normal buffer
* Tweaks almost all rendering settings (especially HDR rendering, bloom, blur, ...)
* Fixes that the blur shader was not considering the correct texel sizes for the given rendertargets
* Moves bloom from the post pass to the pre-post pass
* Moves vignette from the post pass to the pre-post pass
* Overhauls brightness-/high-pass for bloom
* Tweaks many rendertarget sizes and settings for various post-processing effects
* Fixes that bloom was applied to the sky
* Adds debug text for the currently active shader debug mode to the HUD
* Adds lightshafts render target to the debug system
* Fixes that the noise texture used for the film grain effect was linearly interpolated
* Adds various new shader helper methods for calculating block light (and other things)
* ...
Enables chromatic aberration support and fixes broken skyband texture.
Adds some minor SSAO related cleanups.
Adds some minor cleanups and fixes that textured blocks were no longer considering vertex colors (lead to unshaded blocks in the inventory for example).
Adds some additional shader debug features and cleanups.

* Adds two additional shader include files - one for uniforms and one for defines which get appended to vertex and fragment shaders
* All generated shaders sources are from now on being dumped to the logs directory during compilation - so debugging via AMD's GSA gets easier
* Optimizes how the block hints get checked and makes sure all defines are passed in with the correct types
Drastically reduces SSAO intensity.
Fixes that the SSAO 4x4 blur filter was not centered around each texel and thus caused edge artifacts.
Adds that the SSAO algorithm supports varying noise and sphere sample sizes.
Fixes and restructures some debug shader related things and also disables the baked occlusion for the deferred pass if SSAO is enabled. Also tweaks SSAO parameters of course...
Increases film grain intensity slightly.
Tweaks bloom (adjusts settings and adds an additional downsampling pass).

* Doubles specular intensity for water
numerous bugfixes in pathfinder + multi level mazes