Changed block IDs from byte to short.
Made 16BitSparseArray default. Fixes #410.
- use 16-bit-dense-array instead of sparse array as @mbrotz suggested.
Adds some more fixes and tweaks in the World Renderer class.

* Fixes that "pendingChunks" was never reset to false and thus caused the chunksInProximity list to be recreated each frame
* Removes the no longer necessary chunk mesh disposal while adding chunks to the render queues
* Adds that chunk meshes get removed from the VRAM via dispose() when leaving the chunksInProximity list
* Renamed some enums for consistency
Fixes broken FBO error handling and removes exception if something goes wrong so the application does not exit instantly.

* Adds missing "GL_FRAMEBUFFER_UNSUPPORTED_EXT" error case
Adds flag to hide/show the hud to the config file as a debug flag. Also fixes that hiding the HUD or first person view elements via the H key could become inconsistent (first person view is visible while the hud is not and the other way around - and there was no way to fix it without touching the config file).
Merge pull request #595 from skaldarnar/lightAndShadow

L&S content (art assets)
Fixes that billboards were falsely treated as transparent objects - which they are not (they us alpha reject) and adds refractive water effect for default water blocks - aside various other water related tweaks. Most likely fixes #537.

* Water blocks are now translucent again using a slightly refractive effect (using the default texture for perturbation)
* Fixes that billboards were treated as non-opaque (so they were not rendered to the opaque scene rtt (and were thus not visible while looking through blend materials - like water)
* Removes that water became opaque while swimming - this is no longer needed
* Fixes that the fresnel term used for blending between the reflection and refraction target could become invalid
* Changes how swimming and water rendering is treated
Renamed some misleadingly called members and enum variables.
Fixes the completely broken Perlin Noise Map Generator class (there was break missing when choosing the chunk generators to use - so there were actually two worlds being generated on one chunk). Absurd! But I liked the dense forests... Maybe...

* Puts back my name in the header of the Perlin Terrain Generator classes
Fixes that only water blocks were treated correctly as transparent objects - will add real refraction support for those materials later on.
Fixed that the offset for the block damaged overlay was not calculated correctly (could become 10 which points to a tile not part of the damage effect in the atlas).
Defers loading of various chunk related textures and texture atlases so they can be exchanged in mods.
Never write alpha blend materials to the depth buffer - fixes issues with post effects not being applied correctly when looking through ice or water.
Adds sobel and ssao fbos to the debug shader.
Fixes that the shadows in the reflection target (used for the water reflection) flickered when moving from chunk to chunk since the shadow map was updated after the reflection got rendered.
Merge pull request #534 from skaldarnar/BlockIDs

Changed block IDs from byte to short.
Adds support for arbitrary (uniformly) sized texture atlases. Just adjust ATLAS_SIZE and TILE_SIZE in the Block class. Smaller tile textures get up-scaled, while large ones keep their quality.
Adds that the texture atlas gets configured dynamically according to the tiles being loaded when entering a world. This means... If there is one tile with a resolution of 1024x1024 px, the block loader will try to generate an atlas containing tiles with an overall resolution of 1024x1024 px. Smaller tiles get automatically up-scaled to this resolution. If that's not possible, the tile size is dynamically reduced until all tiles fit into the texture atlas. This should allow the creation of hires texture packs/mods just by overwriting the existing textures.

* Adds a new setting to the rendering config (see maxTextureAtlasResolution = 4096) which can be used to specify a maximum texture atlas size - if not all tiles for a given resolution fit in this atlas, the tiles get automatically scaled down until all pieces fit into the atlas. Since ultra hires texture packs won't work on all platforms with enough tiles being available, this can be used to unlock absurdly size texture atlases on high-end GPUs
* Removed 16x16 px size constraint for tiles
* Removed maximum tile constraint of 256 from the Block Loader class (no longer needed due to the dynamic rescaling of the atlas)
Adds that vertex colors in chunks get packed in one uint32 instead of 4 floats... Makes your GPU happy. I guess...
Adds some cleanups with regard to the Chunk UV layout.