Add compute shader particle simulation

[jalberse]

Our current particle simulation is CPU bound, and thus limited to about 7000 particles without slowing the framerate. That's rather low. We should build out a particle simulation that leverages the GPU through a compute shader, which should allow for hundreds of thousands of particles.

[jalberse]

It would be good to get a lorenz attractor simulation going, and then add in collisions with meshes.