Talk about namespaces and unignoring

It was not obvious to at least one person that namespaces need to be
unignored just like classes and methods.  Add an explicit reference to
that in the docs.

Also add something to unignore all classes in the example that shows how
to ignore all classes, as that might not be obvious.

Fixes #193

Doc/Manual/SWIG.html

@@ -2255,6 +2255,21 @@ the following approach could be taken:
 </pre>
 </div>
 
+<p>
+If <tt>Star</tt> was in the <tt>Galaxy</tt> namespace, you would need
+to unignore the namespace, too, and add the namespace to all the
+renames:
+</p>
+
+<div class="code">
+<pre>
+%rename("%s") Galaxy;
+%rename("%s") Galaxy::Star;
+%rename("%s") Galaxy::Star::Star;
+...
+</pre>
+</div>
+
 <p>
 Another approach which might be more suitable as it does not require naming all the methods in the
 chosen class is to begin by ignoring just the classes. This does not add an explicit ignore to any
@@ -2266,6 +2281,7 @@ members of the class, so when the chosen class is unignored, all of its methods
 %rename($ignore, %$isclass) ""; // Only ignore all classes
 %rename("%s") Star; // Unignore 'Star'
 %include "myheader.h"
+%rename("%s", %$isclass) ""; // Stop ignoring all classes
 </pre>
 </div>