Added WSF_RESPONSE_HANDLER based on WSF_RESPONSE_MESSAGE

The descendant has to implement the function

    response (ctx: C; req: WSF_REQUEST): WSF_RESPONSE_MESSAGE

Added related features and class in WSF_ROUTER to be able to use agent easily.

library/server/wsf/router/wsf_response_handler.e

@@ -0,0 +1,48 @@
+note
+	description: "[
+				Request handler object which is called by a WSF_ROUTER
+				A response handler should implement the method
+				
+					response (ctx: C; req: WSF_REQUEST): WSF_RESPONSE_MESSAGE
+
+					
+				The class is generic, this way one can use a custom WSF_HANDLER_CONTEXT if needed
+		]"
+	date: "$Date$"
+	revision: "$Revision$"
+
+deferred class
+	WSF_RESPONSE_HANDLER [C -> WSF_HANDLER_CONTEXT]
+
+inherit
+	WSF_HANDLER [C]
+
+feature -- Execution
+
+	response (ctx: C; req: WSF_REQUEST): WSF_RESPONSE_MESSAGE
+		require
+			is_valid_context: is_valid_context (req)
+		deferred
+		ensure
+			Result_attached: Result /= Void
+		end
+
+feature -- Implementation
+
+	execute (ctx: C; req: WSF_REQUEST; res: WSF_RESPONSE)
+			-- Execute request handler	
+		do
+			response (ctx, req).send_to (res)
+		end
+
+note
+	copyright: "2011-2012, Jocelyn Fiat, Javier Velilla, Eiffel Software and others"
+	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
+	source: "[
+			Eiffel Software
+			5949 Hollister Ave., Goleta, CA 93117 USA
+			Telephone 805-685-1006, Fax 805-685-6869
+			Website http://www.eiffel.com
+			Customer support http://support.eiffel.com
+		]"
+end