changing the second parameter in directory_map to an integer that controls recursion depth.

A depth of 0 is fully recursive to maintain backward compatibility with the boolean values.
diff --git a/user_guide/helpers/directory_helper.html b/user_guide/helpers/directory_helper.html
index eae2c52..3b70799 100644
--- a/user_guide/helpers/directory_helper.html
+++ b/user_guide/helpers/directory_helper.html
@@ -78,10 +78,10 @@
 
 <p class="important"><strong>Note:</strong> Paths are almost always relative to your main index.php file.</p>
 
-<p>Sub-folders contained within the directory will be mapped as well.  If you wish to map
-only the top level directory set the second parameter to <var>true</var> (boolean):</p>
+<p>Sub-folders contained within the directory will be mapped as well.  If you wish to control the recursion depth,
+you can do so using the second parameter (integer). A depth of 1 will only map the top level directory:</p>
 
-<code>$map = directory_map('./mydirectory/', TRUE);</code>
+<code>$map = directory_map('./mydirectory/', 1);</code>
 
 <p>By default, hidden files will not be included in the returned array.  To override this behavior, 
 you may set a third parameter to <var>true</var> (boolean):</p>