stringy

Includes fast methods for endswith, startswith, split, strip, find
and count. Implementations of split and strip from the wiki and book.
Implementation of find and count use python's fastsearch.
Usage is:

> stringy = require "stringy"
> = stringy.strip(" asdf ")
asdf

> = table.concat(stringy.split("aXbXc", "X"), "|")
a|b|c

> = stringy.startswith("asdf", "as")
true
> = stringy.endswith("asdf", "as")
false