Simplify CMS_SERVICE initialization, and CMS server (launcher).

Renamed "layout" lib as "app_env" with APPLICATION_ENVIRONMENT interface.
  applied changed to callers.
Added CMS_THEME.has_region (a_name): BOOLEAN to know if a region is declared in a defined theme.

library/app_env/src/application_layout.e

@@ -0,0 +1,23 @@
+note
+	description: "See {APPLICATION_ENVIRONMENT}."
+	date: "$Date$"
+	revision: "$Revision$"
+
+class
+	APPLICATION_LAYOUT
+
+obsolete
+	"Use APPLICATION_ENVIRONMENT [April/2015]"
+
+inherit
+	APPLICATION_ENVIRONMENT
+
+create
+	make_default,
+	make_with_path,
+	make_with_directory_name
+
+note
+	copyright: "2011-2015, Javier Velilla, Jocelyn Fiat, Eiffel Software and others"
+	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
+end