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/ferguson2/index.html

@@ -707,9 +707,9 @@ make it more flexible by a wrapper program.</p>
 <div id="parsersubtlety">
 <h3 id="a-parser-subtlety-that-could-cause-confusion">A parser subtlety that could cause confusion</h3>
 </div>
-<p>The parser is in a sense rather rudimentary but allows for both interactive and
-automatic (e.g. via the <a href="(https://github.com/ioccc-src/temp-test-ioccc/blob/master/2020/ferguson2/recode.c)%20program">recode</a> input. This does mean that
-something like the following can happen:</p>
+<p>The parser is in a sense rather rudimentary but allows for both interactive and automatic
+(e.g., via the <a href="https://github.com/ioccc-src/temp-test-ioccc/blob/master/2020/ferguson2/recode.c">recode</a> program) input.
+This does mean that something like the following can happen:</p>
 <pre><code>    $ ./prog -
     Ring 1: 1AB
     Setting 1: Position 1: Ring 2: 2CD