Added support for user, user_roles, page, blog export and import.

Added basic support for comments, for now mainly viewing comments from database (no submission forms yet).
Added first simple wikitext filter (render wikitext content as xhtml).
Ensure response content type is text/html with utf-8 charset.

modules/comments/persistence/cms_comments_storage_i.e

@@ -0,0 +1,38 @@
+note
+	description: "Interface for accessing comments from database."
+	date: "$Date$"
+	revision: "$Revision$"
+
+deferred class
+	CMS_COMMENTS_STORAGE_I
+
+feature -- Error Handling
+
+	error_handler: ERROR_HANDLER
+			-- Error handler.
+		deferred
+		end
+
+feature -- Access
+
+	comment (a_cid: INTEGER_64): detachable CMS_COMMENT
+		require
+			a_cid > 0
+		deferred
+		end
+
+	comments_for (a_content: CMS_CONTENT): detachable LIST [CMS_COMMENT]
+			-- Comments for `a_content`.
+		require
+			has_id: a_content.has_identifier
+		deferred
+		end
+
+feature -- Change
+
+	save_comment (a_comment: CMS_COMMENT)
+			-- Save `a_comment`.
+		deferred
+		end
+
+end