Adopted convention name and value or values for WSF_VALUE and descendant (WSF_STRING ...)

kept `key' as redirection, and also string as obsolete redirection.
Router: provide a way to pass the request methods without using manifest string, thanks to WSF_ROUTER_METHODS
  so instead of using manifest array or manifest strings, just create an instance of WSF_ROUTER_METHODS
  for convenience, WSF_ROUTER provides a few `methods_...' returning prebuilt WSF_ROUTER_METHODS objects
Improved code related to unicode handling in URL, and parameters (before the framework was doing too much)

library/server/wsf/src/response/wsf_html_page_response.e

@@ -110,7 +110,7 @@ feature -- Element change
 			body := b
 		end
 
-feature {WSF_SERVICE, WSF_RESPONSE} -- Output
+feature {WSF_RESPONSE} -- Output
 
 	send_to (res: WSF_RESPONSE)
 		local
@@ -147,8 +147,20 @@ feature {WSF_SERVICE, WSF_RESPONSE} -- Output
 			res.put_string (s)
 		end
 
+feature -- HTML facilities
+
+	html_encoded_string (s: READABLE_STRING_32): READABLE_STRING_8
+		do
+			Result := html_encoder.encoded_string (s)
+		end
+
 feature {NONE} -- HTML Generation
 
+	html_encoder: HTML_ENCODER
+		once ("thread")
+			create Result
+		end
+
 	append_html_head_code (s: STRING_8)
 		local
 			t: like title