heaps: Add >min-heap, >max-heap.
hashtables.sequences: minor cleanup.
hashtables.identity: minor cleanup.
hash-sets.wrapped: support for "wrapped" hash-sets.
hash-sets.identity: adding identity hashsets.
hash-sets.sequences: adding sequence hashsets.
editors.sublime: Add support for Sublime Editor 2 for MacOSX. Need to add support for Windows.
sequences: adding nths-unsafe.
random: use nths-unsafe in sample.
math.combinatorics: remove duplicate nths-unsafe.
tools.crossref: switch to using identity hash-sets.