Improve particle systems
Currently, we have particle system bindings only for fire. It works more or less for not-so-large campfires. The improvements that are seen:
1. Add binding to scale the particle system with the size of bbox of an object. It should modify all parameters like particle size, velocity and scale speed.
2. Add different types of particle systems for different type of fire, like torches/
This will require the support on server side too to set proper attributes for different kinds of fire.
3. Add support for LOD and limiting number of particle systems that are simultaneously enabled.
In addition, our current fire particle effect is just the demo Ogre effect. It's probably possible to create a much nicer effect ourselves.