Implement three.js for better performance

[lexcast]

The rendering of too many particles on canvas is not ideal for performance #124. A webGL implementation could be the solution and I think three.js is a good lib for this.

PR are welcome, I will try as well. 😉

[fenwick67]

Looks like drawParticles reads two config items for every single new particle, changing this would probably make a bigger difference in performance. The actual draw calls don't seem to be a big deal on my machine.

[lexcast]

thank you @fenwick67