2004-11-18 Max Bowsher <maxb@ukf.net>

2004-11-18  Max Bowsher  <maxb@ukf.net>

	* archive.h (archive::~archive): Define a pure virtual destructor to
	enforce the abstract nature of this class.
	* archive.cc (archive::~archive): Pure virtual destructors require an
	implementation! Add one.
	* io_stream.h (io_stream::destroyed): Remove this severely
	brain-damaged implementation of a weakly-enforced abstract class.
	The pure virtual destructor was strongly enforcing the abstract nature
	anyway.
	* io_stream.cc (io_stream::~io_stream): Empty out horribly pointless
	code from the pure virtual destructor.
	* archive_tar.cc (archive_tar::~archive_tar): Remove all
	reference to the removed "destroyed" member.
	* archive_tar_file.cc (archive_tar_file::~archive_tar_file): Ditto.
	* compress_bz.cc (compress_bz::~compress_bz): Ditto.
	* compress_gz.cc (compress_gz::~compress_gz): Ditto.
	* io_stream_cygfile.cc (io_stream_cygfile::~io_stream_cygfile): Ditto.
	* io_stream_file.cc (io_stream_file::~io_stream_file): Ditto.
	* io_stream_memory.cc (io_stream_memory::~io_stream_memory): Ditto.