Ported fast-ruby project to fast-crystal

Just finished porting most of the benchmarks from https://github.com/JuanitoFatas/fast-ruby to https://github.com/konung/fast-crystal. About 90% ported, minus some stuff that doesn't really apply to Crystal.

I did this while learning Crystal, as an exercise to dive deeper into various aspects of the superb Crystal language. Hope this helps someone as they are learning crystal and coming over from Ruby ( and other languages)