Implement particle systems

[DCxDemo]

Right now we're missing particles support, which is widely used for stuff like fountains. I see 3 possible ways to cover this issue:

1. implement native particles struct aka NS particle chunk in BSP world extension, basically the way original game works.
2. implement a new function to attach particle to a point in the world space and/or introduce new particle node type. this is probably closest to later games.
3. a more hacky and probably less preferred way: thps3 already allows to attach particle system to a DFF bone in qscript. we can spawn a dummy object with a single bone and add particles this way.