fix more broken markdown links

Fixed stuff we broke by mistake, previously.

Ran `make www` to perform the above.

TODO: Fix stuff we broke by mistake doing the above.

TODO: Fix more broken markdown links.

2020/ferguson1/troubleshooting.html

@@ -379,7 +379,7 @@
 <!-- START: this line starts content for HTML phase 21 by: bin/pandoc-wrapper.sh via bin/md2html.sh -->
 
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-<h1 id="troubleshooting-snake">Troubleshooting Snake</h1>
+<p>9 Troubleshooting Snake</p>
 <p>In this file I have a list of a number of possible problems that could show up
 under some situations as well as some things that might appear to be happening
 or be a problem but actually are not. For each one I have included a summary, a