o Reword a bit in a couple of places, to avoid using 'necessary' and
'need' twice in the same sentence.
o Replace <literal> tags with <emphasis> for tag', port' and
`package' (they are really used as FreeBSD-specific terms, not as <literal> text here).
o Expand a paragraph with inline URIs, which result in pretty awkward
line breaks in PDF/PS output, to a <variablelist>. This separates the URIs from the running text, and looks slightly prettier in print output.