reverse() didn't work at all due to bad arg check.
    Fixed that.
    Added Brad Chapman to ACKS file, as the proud new owner of two
        implicitly copyrighted lines of Python source code <wink>.
    Repaired buffer_info's total lack of arg-checking.
    Replaced memmove by memcpy in reverse() guts, as memmove is
        often slower and the memory areas are guaranteed disjoint.
    Replaced poke-and-hope unchecked decl of tmp buffer size by
        assert-checked larger tmp buffer.
    Got rid of inconsistent spaces before open paren in docstrings.
    Added reverse() sanity tests to test_array.py.