Please include the fasthttprouter router

[yourchanges]

Please include the https://github.com/buaazp/fasthttprouter which based on https://github.com/valyala/fasthttp

[lukeed]

fasthttprouter is the fastest router by a long-shot -- recent comparison.

It may be that (a) the author abandoned this repo (because benchmarks are hard to maintain!!), (b) perhaps the author chose not to include it because also authored httprouter (happens, no biggy), or (c) a lot has changed since Go v1.3 (the env for these results).