merge from 1.6 ( html purifier lib )

git-svn-id: http://xe-core.googlecode.com/svn/branches/1.5.0@10579 201d5d3c-b55e-5fd7-737f-ddc643e51545

classes/security/htmlpurifier/docs/proposal-config.txt

@@ -0,0 +1,23 @@
+
+Configuration
+
+Configuration is documented on a per-use case: if a class uses a certain
+value from the configuration object, it has to define its name and what the
+value is used for.  This means decentralized configuration declarations that
+are nevertheless error checking and a centralized configuration object.
+
+Directives are divided into namespaces, indicating the major portion of
+functionality they cover (although there may be overlaps).  Please consult
+the documentation in ConfigDef for more information on these namespaces.
+
+Since configuration is dependant on context, internal classes require a
+configuration object to be passed as a parameter.  (They also require a
+Context object). A majority of classes do not need the config object,
+but for those who do, it is a lifesaver.
+
+Definition objects are complex datatypes influenced by their respective
+directive namespaces (HTMLDefinition with HTML and CSSDefinition with CSS).
+If any of these directives is updated, HTML Purifier forces the definition
+to be regenerated.
+
+    vim: et sw=4 sts=4