improve how markdown code language is commented

We added a space between the markdown triple code mark
and language that was enclosed in HTML comments.

So a line of the form:

````
```<!---c--->
````

became:

````
``` <!---c--->
````

This was done to **help** some code see that the HTML comment
string was not a markdown code specifier.   Not all code
understands this after this changed.  For example, `pandoc(1)`
still forms HTML classes of the form "&lt;!---c--&gt;"
when it encounters the above mentioned change.

We also fixed a problem with `2019/dogon/README.md` regarding
a markdown code block.

We also fixed a problem with `2020/yang/README.md` regarding
a markdown code block.

contact.html

@@ -145,8 +145,16 @@ problem has already been reported. If it has been reported, feel
 free to add a comment to the issue. If you do not find an it has
 been reported, then fee free to open a <a href="https://github.com/ioccc-src/winner/issues">new IOCCC
 issue</a>.</p>
+<p>If you are trying to:</p>
+<ul>
+<li>Comment or make a suggestion on IOCCC rules - (see <a href="faq.html#feedback">FAQ 0.5</a>)</li>
+<li>Comment or make a suggestion on IOCCC guidelines - (see <a href="faq.html#feedback">FAQ 0.5</a>)</li>
+<li>Comment or make a suggestion on IOCCC tools - (see <a href="faq.html#feedback">FAQ 0.5</a>)</li>
+</ul>
+<p>Those FAQ entries will help guide you on how to make public comments
+and suggestion in the relevant places.</p>
 <p>See the above FAQ entries for more details.</p>
-<h1 id="try-mastodon">Try mastodon</h1>
+<h1 id="try-mastodon"><a name="mastodon"></a>Try mastodon</h1>
 <p>You may wish to follow us <a href="https://fosstodon.org/@ioccc">IOCCC on Mastodon</a>
 as we use that platform to announce things such as the opening of a new IOCCC
 as well as winning entries of the IOCCC.</p>