Examples [WIP]

Ok, next pull request coming up!

I've build a buggy version of a quicksort implementation with a quite common bug (neither the `smaller_than` nor the `larger_than` part include the "equal" part. QuickCheck will find this bug.

**Work in Progress:** I don't know how elegant my implementation is. I tried to keep it to my Haskell implementation, which is only 5 lines. This implementation gets kinda messy with conversions between vectors and ranges. I will ask for feedback in the Rust IRC :+1: