WIP: Natvis visualization

[ikrima]

Saw #102 and in case others are looking for the same for visual studio, here's my natvis:
https://gist.github.com/ikrima/1184c75b979cbfa655c0883c0d4ab068

Threw it together for a specific personal debug case but sharing in case it might be useful for someone else (the natvis docs are obtuse)

[sultim-t]

It was not quite working for me from a box, so tweaked it a bit: robin_hood.natvis.txt

Dropping .txt extension and putting it into the Documents\Visual Studio 2022\Visualizers folder should just work for VS22