Added support for path_aliases.

Refactored CMS_MODULE.router (..): WSF_ROUTER design,
  to create only one router object of type CMS_ROUTER.
Added optional CMS_NODE.link: CMS_LOCAL_LINK
Reviewed permissions related to node module.
Refactor and add CMS_STORAGE_SQL(_BUILDER) abstractions
   for implementation relying only on SQL statements.
Factorized sql builder initialization (to work for sqlite and mysql storage builders).
Added CMS_RESPONSE.formatted_string (a_text: READABLE_STRING_GENERAL; args: TUPLE): STRING_32
Added function "translation", but not implemented for now.
Updated indexing notes and comments.
Code cleaning.

src/service/cms_module.e

@@ -66,10 +66,8 @@ feature {CMS_API} -- Module management
 
 feature -- Router
 
-	router (a_api: CMS_API): WSF_ROUTER
-			-- Router configuration.
-		require
-			is_enabled: is_enabled
+	setup_router (a_router: WSF_ROUTER; a_api: CMS_API)
+			-- Setup url dispatching for Current module.
 		deferred
 		end