add a consistent set of text about X11

1993/cmills/index.html

@@ -414,7 +414,7 @@ bugs.html</a>). See the <a href="#original-code">original code</a>
 section below to run the original (the bug also exists here).</p>
 <pre><code>    make alt</code></pre>
 <p>NOTE: this entry requires the <code>X11/Xlib.h</code> header file and the X11 library to
-compile. If you don’t have the X11 installed see the
+compile. For more information see the
 FAQ on “<a href="../../faq.html#X11">X11</a>”.</p>
 <p>To configure how many microseconds to sleep before updates try:</p>
 <pre><code>    make clobber SLEEP=200 alt</code></pre>