Revisited the persistence layer.

Simplified schema to focus on user and node.
Now possible to have sqlite via ODBC and/or mysql support, and select using configuration file.
Updated demo example.

examples/demo/site/config/cms.ini

@@ -1,6 +1,11 @@
-engine=smarty
-site.name=EWF Web CMS
-site.email=your@email.com
-var-dir=var
-files-dir=files
+[layout]
+root-dir=site/www
+themes-dir=site/www/themes
+
+[site]
+name=Eiffel CMS
+email=your@email.com
 theme=bootstrap
+
+[misc]
+smtp=localhost