Added support for base_url (i.e the CMS can be hosted on the root, or sub folder).

Local paths are relative to cms site url (i.e no starting slash).
Favor CMS_RESPONSE.absolute_url and url .. instead of using directly WSF_REQUEST.absolute_script_url and script_url.
Handled unicode truncation issue for logger.
Code cleaning.

examples/demo/modules/blog/cms_blog_module.e

@@ -101,7 +101,7 @@ feature -- Hooks
 		local
 			lnk: CMS_LOCAL_LINK
 		do
-			create lnk.make ("Blogs", "/blogs/")
+			create lnk.make ("Blogs", "blogs/")
 			a_menu_system.primary_menu.extend (lnk)
 		end