Various improvements in the ChParticleEmitter file.
Major feature: new ChRandomShapeCreatorShavings , to create small twisted chips of material, like in shredding processes. The collision is approximated with cluster of spheres for better performance.
The code for parsing the JSON setting file has been segregated into separate files.
This is still under testing.
Various changes, in view of the future settings-based parser for initializing everything.
Still under testing.