Started implementing individual paged layers.
Basic functions for creating/destroying buffers, adding/removing layers and adding elements.
Cleanup: disabled old modifier solution for now.
Added a new modifier NParticleBuffer. This is just a thin wrapper around the NParticleBuffer struct to act as a particle container. Eventually could utilize a better object data system, for now this is ok.
Renamed the modifier to NParticleSystem since it will also define some simulation modes in addition to the actual buffer.
Added applyModifier callback and AcceptsMesh flag so particle system can added on mesh objects. applyMesh is just a stub returning the unmodified mesh.
Added missing draw function in the modifier panel.
Added read/write code for NParticleSystemModifierData and NParticleBuffer.
Added missing DNA files to makesdna.
Updated read/write code for paged buffer for the new layer/page structure.
Basic RNA for paged buffer and nparticle buffer.
Basic particle buffer implementation with RNA for adding and removing attributes.
Basic properties for particle attribute descriptors. Uses a generic function to inject these properties using the nested 'desc' field.
Setter callback for particle attribute data type. Currently just throws an assert failure, later on this should make sure the particle data is converted to the correct type (or simply make datatype read-only).
Collection properties for actual data in particle buffers.
Disabled some unused DNA code for nparticles.
Removed deprecated DNA data inside #if 0 block, C preprocessor doesn't
work with makesdna.
Some renaming and DNA reorganization. Particle attributes now have a
descriptor as well as state data.
Renamed RNA property of the particle system in the psys modifier.
Disabled strict alignment in paged buffer for now, this fails for vector
attributes, needs a nicer way to handle this.