(spam-use-bogofilter-headers, spam-bogofilter-header)

(spam-use-bogofilter-headers, spam-bogofilter-header)
(spam-bogofilter-database-directory): new variables
(spam-check-bogofilter-headers, spam-check-bogofilter)
(spam-bogofilter-register-with-bogofilter)
(spam-bogofilter-register-spam-routine)
(spam-bogofilter-register-ham-routine)
(spam-group-ham-processor-bogofilter-p): new functions for the new
Bogofilter interface
(spam-summary-prepare-exit): use the new Bogofilter functions
(spam-list-of-checks): added spam-use-bogofilter-headers
(gnus-summary-mode-map): removed the spam-bogofilter-score entries
for now