Add ruby implementation as "check"
Add ruby implementation as "check"

The Jack implementation is incredibly slow, and may not actually work so we add a ruby implementation as a check that our impl actually works.  This ruby implementation is a direct transliteration of the Jack one (without the boolean logic decompression as I'm pretty sure that rubys' booleans work).

h-lame/computationclub-mandelbrot,h-lame/computationclub-mandelbrot