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.

src/service/cms_api.e

@@ -246,7 +246,7 @@ feature {NONE}-- Implemenation
 	internal_user_api: detachable like user_api
 			-- Cached value for `user_api'.
 
-feature -- Layout
+feature -- Environment
 
 	module_configuration (a_module_name: READABLE_STRING_GENERAL; a_name: detachable READABLE_STRING_GENERAL): detachable CONFIG_READER
 			-- Configuration reader for `a_module', and if `a_name' is set, using name `a_name'.
@@ -254,7 +254,7 @@ feature -- Layout
 			p, l_path: PATH
 			ut: FILE_UTILITIES
 		do
-			p := setup.layout.config_path.extended ("modules").extended (a_module_name)
+			p := setup.environment.config_path.extended ("modules").extended (a_module_name)
 			if a_name = Void then
 				p := p.extended (a_module_name)
 			else

src/service/cms_service.e

@@ -41,13 +41,11 @@ create
 
 feature {NONE} -- Initialization
 
-	make (a_api: CMS_API)
+	make (a_setup: CMS_SETUP)
 			-- Build a CMS service with `a_api'
 		do
-			api := a_api
+			create api.make (a_setup)
 			initialize
-		ensure
-			api_set: api = a_api
 		end
 
 	initialize
@@ -138,7 +136,7 @@ feature -- Settings: router
 			a_router.handle_with_request_methods ("/theme/", fhdl, router.methods_GET)
 
 
-			create fhdl.make_hidden_with_path (setup.layout.www_path)
+			create fhdl.make_hidden_with_path (setup.environment.www_path)
 			fhdl.disable_index
 			fhdl.set_not_found_handler (agent  (ia_uri: READABLE_STRING_8; ia_req: WSF_REQUEST; ia_res: WSF_RESPONSE)
 				do

src/service/response/cms_response.e

@@ -107,7 +107,7 @@ feature -- Module
 	module_assets_location (a_module: CMS_MODULE): PATH
 			-- Location for the assets associated with `a_module'.
 		do
-			Result := setup.layout.path.extended ("modules").extended (a_module.name)
+			Result := setup.environment.path.extended ("modules").extended (a_module.name)
 		end
 
 	module_assets_theme_location (a_module: CMS_MODULE): PATH