Performance of find methods, comparison with linear search

[Renaud Detry]

> I find your tests awesome. I am totally gonna use it :-) I am just
> gonna replace the linear search by ANN, in order to compare to
> something better. Well, I hope I'll be able to do that soon.

I'm glad to hear it helps.

I didn't put that many (i.e. any) comments in the code, don't hesitate
to ask if something seems strange :-)

Cheers,
Renaud.