operator<< was a friend class that locked the ByteVector, then invoked
hexdump on the bytevector, which used ByteVector::operator[]...which
locked the ByteVector, resulting in a deadlock.
operator<< shouldn't be a friend class anyway. Make hexdump use the
normal public access methods for ByteVector.
Signed-off-by: Zygo Blaxell <bees@furryterror.org>