Bug fixes and code cleanup

-Standardized water/terrain storage to hold height value in alpha
channel and normal in rgb channels
-Water/terrain shaders now generate normals using proper texel size
-Moved full height calculation into terrain shader
-Improved the water shader by adding simplex noise
-Application now release mouse control when it loses focus
Update textures at fixed 30fps

-Textures don't update every frame, instead only update at ~ 30fps