Added weight into to the CMS_LINK and provide a `sort' feature for CMS_MENU and related.

Protected cms service from registering many time the same module type.
Moved library/persistence/implementation/* under library/persistence/.
Moved site/www/themes to site/themes
For SQLite storage driver, auto create sqlite db file using associated sql script (to be completed).
Added code in demo module to reuse storage for module purpose.
Always call sql_post_execution in sql_query and sql_change, and not anymore by the callers.
Removed is_web and is_html from {CMS_SETUP}, it was not used.
Reused SHARED_*_ENCODER in CMS_ENCODERS
Added CMS_API.logger rather than using directly the SHARED_LOGGER.log ...
Centralize the implementation of current_user in CMS_REQUEST_UTIL
Removed the inheritance on WSF_FILTER for node handlers, since it is useless and unused.
Added CMS_NODE_API and CMS_USER_API
Prefix html id for block generated html items with "block-", to avoid css name conflict on "main", "content" or similar.
Code cleaning

library/persistence/implementation/store/database/database_connection_null.e

@@ -0,0 +1,68 @@
+note
+	description: "Null object to meet Void Safe."
+	date: "$Date: 2014-08-20 15:21:15 -0300 (mi., 20 ago. 2014) $"
+	revision: "$Revision: 95678 $"
+
+class
+	DATABASE_CONNECTION_NULL
+
+inherit
+
+	DATABASE_CONNECTION
+		redefine
+			db_application,
+			is_connected
+		end
+
+create
+	make, make_common, make_basic
+
+feature -- Initialization
+
+	make_common
+			-- Create a database handler for ODBC with common settings.
+		do
+			create database_error_handler.make
+			create db_application.login (username, password)
+			db_application.set_hostname (hostname)
+			db_application.set_data_source (database_name)
+			db_application.set_base
+			create db_control.make
+		end
+
+	make (a_username: STRING; a_password: STRING; a_hostname: STRING; a_database_name: STRING; connection: BOOLEAN)
+
+			-- Create a database handler for ODBC.
+		do
+			make_common
+		end
+
+	make_basic (a_database_name: STRING)
+
+			-- Create a database handler for ODBC.
+		do
+			make_common
+		end
+
+
+	login_with_connection_string (a_string: STRING)
+			-- Login with `a_connection_string'
+			-- and immediately connect to database.
+		do
+			make_common
+		end
+
+
+feature -- Databse Connection
+
+	db_application: DATABASE_APPL[DATABASE_NULL]
+			-- Database application.
+
+
+	is_connected: BOOLEAN
+			-- True if connected to the database.
+		do
+			Result := True
+		end
+
+end