Document the new trace-related winedbg commands.

documentation/debugger.sgml

@@ -1514,10 +1514,22 @@ b => 8 bit unsigned hexadecimal integer
 	  </itemizedlist>
 	</para>
       </sect2>
+      <sect2>
+          <title>debug messages</title>
+	      <para>
+               It is possible to turn on and off debug messages as you are debuging using
+               the set command.
+              </para>
+            <screen>
+set + warn win	=&gt; turn on warn on 'win' channel
+set + win	=&gt; turn on warn/fixme/err/trace on 'win' channel
+set - win	=&gt; turn off warn/fixme/err/trace on 'win' channel
+set - fixme	=&gt; turn off the 'fixme' class
+            </screen>
+      </sect2>
 
     </sect1>
 
-
     <sect1 id="dbg-others">
       <title>Other debuggers</title>
 

documentation/debugging.sgml

@@ -17,6 +17,12 @@
           easier, please follow the guidelines described in this
           document.
         </para>
+
+        <para>
+          It is possible to turn on and of debugging output from
+          within the debuger using the set command. Please see the
+          WineDbg Command Reference section for how to do this.
+        </para>
       </note>
 
       <important>