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/configuration/cms_default_setup.e

@@ -84,7 +84,7 @@ feature {NONE} -- Initialization
 	initialize_modules
 				-- Intialize core modules.
 		local
-			m: CMS_MODULE
+--			m: CMS_MODULE
 		do
 			-- Core
 --			create {BASIC_AUTH_MODULE} m.make