Brainfuck

As the name implies, this is a very simple Brainfuck interpreter written in Nit.

Yes, it is (mostly) useless, but it might serve as an example of a simple Nit program.

Question : Do I leave it in Contrib, or should I move it to examples ?
Pour sauver des caractères, la dizaine de lignes précédente pourraient être remplacée par:

`new HashSet[Char].from("><[].,+-".chars)`