[armedbear-devel] Minor doc patch for table of contents

The basic TOC should be simple. It seems that pdflatex automagically makes the TOC entries to be hyperlinks, so this should be a relative no-brainer? We can use a more elaborate toc-package later if need be. I haven't pushed this in yet, because the manual is sort-of-Mark's turf, so I'm getting my feet wet before committing directly. ;)