remove questionable sentence

I could not tell whether it was meant to be humorous, or if it simply was a mistake. Regardless, I think it does not add much. If Speed needs to be defended, perhaps something better would do. For now, I remove.
this info was given in the preceding paragraph
virtualenv refers both to the tool and the concept
improve paragraph
use 'rfc' role to link to the RFCs; this fixes one link, for free
update some links and fix others
fix link
update link
use cross-references to fix some links

Also fix grammar, and add a bit of consistency regarding formatting.
make it clear where the link goes
fix links
update links
fix broken link
rm broken link; could not find existing equivalent
fix broken links
rm reference to broken link
fix wrong highlighting
typo
fix markup
missing word