Support for VCC collision checking against point clouds

vamp-vcc is a cool new collision-checking algorithm for robots against point clouds. We should include it!

Performance enhancements to try:

• Flatten search using index arithmetic to avoid having a layer for each dimension.
  • note: this would make MVTs immutable. A worthy tradeoff? Or perhaps we write a custom allocator...
• Order collision checks to move radially from the center.
• Use locality-respecting order for buffers to improve memory locality.
• Use gather instructions for parallel memory loading.
• (later) Play around with other extension ideas....