htmlpurifier update - compatibility issue with language library autoloader

library/HTMLPurifier/ConfigSchema/schema/HTML.AllowedElements.txt

@@ -4,12 +4,17 @@ VERSION: 1.3.0
 DEFAULT: NULL
 --DESCRIPTION--
 <p>
-    If HTML Purifier's tag set is unsatisfactory for your needs, you
-    can overload it with your own list of tags to allow.  Note that this
-    method is subtractive: it does its job by taking away from HTML Purifier
-    usual feature set, so you cannot add a tag that HTML Purifier never
-    supported in the first place (like embed, form or head).  If you
-    change this, you probably also want to change %HTML.AllowedAttributes.
+    If HTML Purifier's tag set is unsatisfactory for your needs, you can
+    overload it with your own list of tags to allow.  If you change
+    this, you probably also want to change %HTML.AllowedAttributes; see
+    also %HTML.Allowed which lets you set allowed elements and
+    attributes at the same time.
+</p>
+<p>
+    If you attempt to allow an element that HTML Purifier does not know
+    about, HTML Purifier will raise an error.  You will need to manually
+    tell HTML Purifier about this element by using the
+    <a href="http://htmlpurifier.org/docs/enduser-customize.html">advanced customization features.</a>
 </p>
 <p>
     <strong>Warning:</strong> If another directive conflicts with the