The very first version of gridding in Halide.

Actually, it is second one, it is a reimplementation from new grounds.

This commit is to mark the start.

I chose bilateral_grid from Halide example applications (apps) because it is 1) uses the same Halide tools as gridding would and 2) relatively simple.
Merge branch 'master' of github.com:SKA-ScienceDataProcessor/RC