Terrain Manager

Ive now created a "Working" Terrain class. It can create some basic chunks but the chunk system (which I explained in the Issue) is not implemented so you have to set the position manual in the Terrain.AddChunk(..)

I also added test terrain and I can say Im not a good artist but I will get a nicer terrain. If you know why the floor is so pixelated then tell me please!

Just a quick git question. I have forked the project, created an own branch but when I sync it, it does not sync your latest commits. What am I doing wrong?