Create a benchmark based on inflate algorithm

[nikomatsakis]

@eddyb has implemented the inflate algorithm -- somewhere (he told me, but I'm too lazy to scrape my IRC logs and go find it). I think in the piston project. :) We should make a benchmark from this applied to some representative input.

[nikomatsakis]

@eddyb -- you up for that? you just need a directory with some standalone-ish code that we can run cargo bench on.

[eddyb]

https://github.com/PistonDevelopers/inflate