#12 Better support for code / preformatted text

[Philippe Andersson]

Another HTML I often use in manuals is the "<pre>" tag,
for showing code samples or other preformatted text.

I was able to reproduce the effect in STML by enclosing
each line within "::" tags, and by adding a "~~" at the
end, but that's rather cumbersome.

Is there any better alternative ?