Handles arrays of scalars or objects using integer ranges as index

 Array::IntSpan brings the speed advantages of Set::IntSpan to
 arrays. Uses include manipulating grades, routing tables, or any other
 situation where you have mutually exclusive ranges of integers that
 map to given values.
 .
 Array::IntSpan is also able to consolidate ranges
 by comparing the adjacent values of the range. If 2 adjacent values
 are identical, the 2 adjacent ranges are merged.