Log Message:
Update to 0.9.4 (note that the author changed versioning system,
our last version was 0.84).

	* Update documentation.
	* Move Bayes stuff into its own file.
	* Fix NaN exception: if list is empty, use zero for probability.
	* Make extrema array (keepers) variable size.  Needs more work.
	* Add SYSLIBS to the makefile.
	* Fix gcc-ism in dbg.c (ptr arithmetic on void*).
	* Fix off-by-one in html tag check.
	* Fix unaligned access in libdb.
	* Fix bug in -d handling for text and libdb.
	* Autodetect mailbox type and deprecate the -m option.
	* Ditch the builtin libdb locks, use fcntl instead.
	* Fix memory leak in dbtext.
	* Fix some trivial issues with the lexer:
	  - Be more strict about recognizing IP addresses.
	  - Do case-insensitive header name comparisons.
	* Fix multiple database closure with mbox format.
	* Fix a bogus assert in passthrough.
	* Add heap checking in debug mode.
	* Fix bug in -N mode which made it act the same as -S.
	* Support maildir style folders.
	* Fix bug in multiple message registration.
	* Improve error reporting and clarify some messages.
	* Package preformatted manpage instead of XML.
	* Remove single message per invocation restriction.