Added debug clause to detect in WSF_ROUTER.map_with_request_methods the existing conflicts with similar mapping.

Added smart handling of HEAD request.
Exported some internal features of WSF_REQUEST and WSF_RESPONSE to respectively WSF_REQUEST_EXPORTER and WSF_RESPONSE_EXPORTER

library/server/wsf/src/wsf_response.e

@@ -31,6 +31,8 @@ feature {NONE} -- Initialization
 			wgi_response := r
 		end
 
+feature {WSF_RESPONSE_EXPORTER} -- Properties		
+
 	wgi_response: WGI_RESPONSE
 			-- Associated WGI_RESPONSE