This package provides utility routines for handling integer sets and maps.

The main classes are `IntSet`

which represents a set of 32-bit integers
(int values), `IntIterator`

which is an iterator over a sequence of 32-bit
integers, `IntHashMap`

which is a map from 32-bit integers to arbitrary
objects, and `IntToIntMap`

which is a map from 32-bit integers to 32-bit
integers.

The package name is a pun on the conventional use by mathematicians
of the symbol **Z** to denote the set of all natural integers.

*Michael H. Kay
Saxonica Limited
9 January 2014*