Dual cone spotlight
New light type: Capsule light! :)
Projective point light (projects image as light).
Projective spotlight
Lights: Depth test + no more "is inside?" test.

Depth test is done despite depth buffer being bound as shader resource
:) Yay D3D11! Lights always render with front face culling (except for
full screen ones), removing the need to change rasterizer state
depending on whether camera is inside light volume or not.
More useful OBJ-loader + tiny bug :)

OBJ loader now handles batches better. Didn't bother to fix material
because it's not used anyway. Should also work with negative face
indices. It turns out the test model I was using was messed up so I
can't know for sure. But the main thing I wanted is done and it should
be a good foundation if further work is required. Oh, and I also found a
tiny bug in the directional light shader that was fixed by a mighty
minus.
Merged Andreas into master.