[1.3.0] Huge upgrade, (X)HTML Strict now supported

+ Transparently handles inline elements in block context (blockquote)
! Added GET method to demo for easier validation, added 50kb max input size
! New directive %HTML.BlockWrapper, for block-ifying inline elements
! New directive %HTML.Parent, allows you to only allow inline content
- Added missing type to ChildDef_Chameleon
. ChildDef_Required guards against empty tags
. Lookup table HTMLDefinition->info_flow_elements added
. Added peace-of-mind variable initialization to Strategy_FixNesting

git-svn-id: http://htmlpurifier.org/svnroot/htmlpurifier/trunk@560 48356398-32a2-884e-a903-53898d9a118a

library/HTMLPurifier/ChildDef/Required.php

@@ -20,7 +20,10 @@ class HTMLPurifier_ChildDef_Required extends HTMLPurifier_ChildDef
             $elements = explode('|', $elements);
         }
         $elements = array_flip($elements);
-        foreach ($elements as $i => $x) $elements[$i] = true;
+        foreach ($elements as $i => $x) {
+            $elements[$i] = true;
+            if (empty($i)) unset($elements[$i]);
+        }
         $this->elements = $elements;
         $this->gen = new HTMLPurifier_Generator();
     }