RFC 1924 describes a compact, fixed-size representation of IPv6
addresses which uses a base 85 number system. This module handles some
of the uglier details of it.

The base 85 numbers (from 0 to 84) are as follows:

    0..9 A..Z a..z ! # $ % & ( ) * + - ; < = > ? @ ^ _ ` { | } ~

At the moment, there's not much in this module. But it should be
sufficient for the purposes of RFC 1924.

-Anton