(updated) COVID-19 fast/small resources page

[Rich Kulawiec <rsk () gsp org>]

It's here: http://www.firemountain.net/covid19.html

There's now a link to Job Snijders' "Internet Operations During
Pandemics" PDF, better coverage of mapping/tracking, links to
every US state's public health agency, links to Canada and Mexico's
CDC-equivalents, etc.  I also fixed the character encoding.
I may move the commentary at the bottom elsewhere: I'm trying to
keep this page very lightweight, which is why there are no graphics,
scripting, or anything else.

Comments/fixes/additions to me, off-list please.

---rsk