Make ^NOTE in markdown/html files bold

2013/birken/index.html

@@ -415,7 +415,7 @@ like back in 2013 (with a configurable speed). If you wish to use the original
 version see the <a href="#original-code">original code</a> section below.</p>
 <h2 id="to-use">To use:</h2>
 <pre><code>    ./birken.alt &lt; 17_columns_wide_paint_by_numbers_file</code></pre>
-<p>NOTE: if your terminal is messed up after running this (perhaps from exiting
+<p><strong>NOTE</strong>: if your terminal is messed up after running this (perhaps from exiting
 before it finishes) try using <code>reset</code> to restore the terminal. This will clear
 the screen.</p>
 <h2 id="try">Try:</h2>