Blender Git Loki

Disabled data access in particle RNA.

Only the general attribute descriptions and state instance can be
accessed from plain bpy now. For detailed data read/write the bparticles
module has to be used.

This was forced by a change to collection iterators, which essentially
makes them unsuitable for anything other than ListBase and arrays
(state attributes and particle data in this case). It may be possible
to reeanble this later, but generally bparticles is the better approach.