Make FBX Skinned Mesh Load Animator Part 3

Final part: We finish making the FBX Loader/Animator based on Wil Motil's code and using Assimp and making a shader based on monogame/xna skinned shader (fog, 1-3 lights, normal mapping support, eye-gloss support) with a brief explanation of how to use this to do animation like we did with the other monogame skinned mesh tutorials. The advantage of this is it will support most FBX exports including multi-skinned-mesh and lays a foundation for making various shaders to handle different material properties (automatically).