#1 IFML is not fully XML-ified

The pseudo-HTML embedded in IFML strings is providing
semantic markup, but it will not be parseable by
commodity XML parsers. Conversion between IFML and
other standard languages may require that feature.
(For example, to enable bold text in Inform strings.)
The square-brackets should be dropped, and true XML
namespaces (like <xhtml:p>) should be used instead.