SPS Finished

I'm happy to announce to you that the first finished version of the SPS in the core is now released.

Everything is documented here with examples, in my bad english :  https://github.com/BabylonJS/Documentation/blob/master/content/tutorials/03_Advanced/Solid_Particle_System.md

Soon here : http://doc.babylonjs.com/tutorials/Solid_Particle_System

Have fun