Added options for chroot and setting the server uid/gid.

Are you interested in this pull? It adds the ability to chroot() and setuid()/setgid() the server process. Usage is described in the README, along with some notes for setup. Only tested on Linux, it will only work on *nix OSes (this is checked in the code).

I came across your script when I was looking to set up a very quick and easy IRC server for a handful of users, and it fit the bill nicely. Being security conscious though, I like to run any server apps in a container with minimial privileges.

Anyway, if it looks like something you'd pull, I'll clean it up a bit more and apply any suggestions you have.