Switch to particle kernel function with compact support

This gives us opportunities to improve performance, since particles have a finite distance over which they
provide a contribution to the scene. This also includes kernel function and its derivative for use by subclasses.
Much better colors for 'rings'
Build fixes for C++ examples on Linux
Big-endian portability fix

Tested on MIPS OpenWRT router
Consistency fixes for ParticleEffect
Adding nanoflann KD-tree library

https://code.google.com/p/nanoflann/

From nanoflann-1.1.7
Use .h suffix, for consistency
Remove broken dynamic blocksize from pooled allocator

This was causing a compiler warning
KD-tree particle index
Merge branch 'master' of https://github.com/scanlime/fadecandy