Bit-Vector Iteration

This module provides iteration protocols for BitVec, including:

• extension of existing bit-vectors with new data
• collection of data into new bit-vectors
• iteration over the contents of a bit-vector
• draining and splicing iteration over parts of a bit-vector.

BitVec implements Extend and FromIterator for both sources of individual bits and sources of T memory elements.

The by-value bool iterator is defined in boxed::iter, rather than here. The Drain and Splice iterators remain here in their original location.