public static class Configuration.IntegerRanges
A class that represents a set of positive integer ranges. It parses
strings of the form: "2-3,5,7-" where ranges are separated by comma and
the lower/upper bounds are separated by dash. Either the lower or upper
bound may be omitted meaning all values up to or over. So the string
above means 2, 3, 5, and 7, 8, 9, ...