[1.7.0] Add documentation for the Tidy functionality

- Make specifying the child property for ElementDef unnecessary when overloading content_model or content_model_type
- Add necessary includes to Tidy module files
- Move div@align fix to Tidy_Proprietary
- Future proof attrTransform.php by setting doctype to strict

git-svn-id: http://htmlpurifier.org/svnroot/htmlpurifier/trunk@1071 48356398-32a2-884e-a903-53898d9a118a

library/HTMLPurifier/HTMLModule/Tidy/Proprietary.php

@@ -0,0 +1,27 @@
+<?php
+
+require_once 'HTMLPurifier/HTMLModule/Tidy.php';
+
+class HTMLPurifier_HTMLModule_Tidy_Proprietary extends
+      HTMLPurifier_HTMLModule_Tidy
+{
+    
+    var $name = 'Tidy_Proprietary';
+    var $defaultLevel = 'light';
+    
+    function makeFixes() {
+        $r = array();
+        
+        // {{{ // duplicated from XHTMLAndHTML4: not sure how to factor out
+            $align_lookup = array();
+            $align_values = array('left', 'right', 'center', 'justify');
+            foreach ($align_values as $v) $align_lookup[$v] = "text-align:$v;";
+        // }}}
+        $r['div@align'] = new HTMLPurifier_AttrTransform_EnumToCSS('align', $align_lookup);
+        
+        return $r;
+    }
+    
+}
+
+?>