(spam-ifile-path, spam-ifile-database-path)

(spam-ifile-path, spam-ifile-database-path)
(spam-bogofilter-path): Use define-obsolete-variable-alias instead of
make-obsolete-variable.
(spam-bsfilter-path, spam-bsfilter-program)
(spam-spamassassin-path, spam-spamassassin-program)
(spam-sa-learn-path, spam-sa-learn-program): Rename variables.  Don't
use "path" inappropriately.
(spam-check-spamassassin, spam-spamassassin-register-with-sa-learn)
(spam-check-bsfilter, spam-bsfilter-register-with-bsfilter): Use new
variable names.