* lisp/mh-e/mh-junk.el (mh-spamassassin-*list): Remove support for SpamAssassin 2.20. (SpamAssassin 3.0 was released in 2004.) This change updates both the flags for sa-learn and the comments about how the current version works. This change reverts part of a change made in 2003 that added support for what was even then an "old version of spamassassin."