Refactor|Renderer: Use C++11 for iterating contacted lights list
Documentation|Client: Typos and todo notes
Refactor|Renderer: Prepare common MVP matrix for the frame

This is static throughout the frame, so everyone can use the same one.
Model Renderer: Give light vectors to the model shader

Working on lights. Now the light vectors (up to 4) contacting the model
are applied in the shader. Note that the light directions are
transformed to model space by ModelRenderer.