Moved anonymous namespace functions into SFML shader
Updated comments and started virtualising methods
Virtualising more methods
Updated to GLEW 1.9.0
Moved GlCheck back to .cpp
Added SFML Shader_3_2 for an OpenGL 3.2 implementation of shaders
Added SFML Shader_2 for an OpenGL 2.0 implementation of shaders
Required shader to be used for rendering to RenderTarget
Removed bind textures and added OpenGL shader location variables to Shader

Also ApplyProjectionMatrix
Removed bind method from Texture as it should be done in Shader