1.0.13.22: text tweaks

1.0.13.22: text tweaks
	* logged a bug
	* searched for sbcl-devel references and added notes about
	  the need to subscribe (since the mailman bounce message is
	  particularly unhelpful, and I periodically get mail from
	  frustrated would-be posters)
	* fixed a few typoes
	* revised a few passages, and completely gave up on trying to
	  summarize SBCL performance in a paragraph in the man page