Removed two sequencetools functions.

    * sequencetools.iterate_sequence_nwise_cyclic()
    * sequencetools.iterate_sequence_nwise_wrapped()

Use ...

    * sequencetools.iterate_sequence_nwise(..., cyclic=True)
    * sequencetools.iterate_sequence_nwise(..., wrapped=True)

... instead.

CHANGE: should be noted in the 2.15 change log.