fix HTML problems associated with leading ---'s

Please do not use "**---**" in markdown lines to separate sections.

This causes `pandoc(1)` to generate "**\<hr />**".

The "**\<hr />**" has no effect in standard HTML 5 and interacts
badly with unquoted attribute values.

If a horizontal line is really needed, use "**\<hr>**".

If a short line is needed, use: "**\<hr
style="width:10%;text-align:left;margin-left:0">**"

2013/hou/index.html

@@ -264,8 +264,10 @@ header has a comment line for non-standard-compliant viewers (specifically, my
 old HDRShop 1.0). And there is a nice text message saying “please wait…”.
 Despite the messy look, <a href="a.c">a.c</a> and <a href="hou.c">hou.c</a> compile warning-free
 (<a href="hou.c">hou.c</a> even wastes 18 bytes on <code>#include&lt;stdio.h&gt;</code> just for <code>putchar(3)</code>).
-<a href="a.c">a.c</a> compiles mostly clean in the C99/ANSI modes of clang and gcc (with <code>-Wall --pedantic</code>). The only warning generated is a pedantic one: <code>"string constant too long"</code>.</li>
+<a href="a.c">a.c</a> compiles mostly clean in the C99/ANSI modes of clang and gcc (with:</li>
 </ul>
+<pre><code>-Wall --pedantic</code></pre>
+<p>The only warning generated is a pedantic one: <code>"string constant too long"</code>.</p>
 <h3 id="comments-and-why-obfuscated">Comments and why obfuscated</h3>
 <ul>
 <li>Both the compression and the rendering use mathematically involved algorithms.