correct PONG replies

--HG--
branch : nmdc-ircfrontend

TODO.txt

@@ -9,6 +9,8 @@ PRE-RELEASE
 
 - andchat: system message styling
 
+- andchat: WHO list doesn't get /cleared/ on room quit+autojoin
+
 - part all nicks upon upstream server disconnection
 
 - test the current password auth

server.go

@@ -198,7 +198,7 @@ func (s *Server) handleCommand(command string, args []string) {
 
 	switch command {
 	case "PING":
-		s.reply(rplPong)
+		s.reply(rplPong, strings.Join(args, " "))
 
 	case "PONG":
 		// do nothing
@@ -571,14 +571,17 @@ func (s *Server) reply(code replyCode, args ...string) {
 		s.writeClient(fmt.Sprintf(":%s 371 %s :%s", s.name, s.upstreamLauncher.Self.Nick, args[0]))
 	case rplVersion:
 		s.writeClient(fmt.Sprintf(":%s 351 %s %s", s.name, s.upstreamLauncher.Self.Nick, args[0]))
+
 	case rplMOTDStart:
 		s.writeClient(fmt.Sprintf(":%s 375 %s :- Message of the day - ", s.name, s.upstreamLauncher.Self.Nick))
 	case rplMOTD:
 		s.writeClient(fmt.Sprintf(":%s 372 %s :- %s", s.name, s.upstreamLauncher.Self.Nick, args[0]))
 	case rplEndOfMOTD:
 		s.writeClient(fmt.Sprintf(":%s 376 %s :- End of MOTD", s.name, s.upstreamLauncher.Self.Nick))
+
 	case rplPong:
-		s.writeClient(fmt.Sprintf(":%s PONG %s %s", s.name, s.upstreamLauncher.Self.Nick, s.name))
+		s.writeClient(fmt.Sprintf(":%s PONG %s %s", s.name, s.upstreamLauncher.Self.Nick, args[0]))
+
 	case errMoreArgs:
 		s.writeClient(fmt.Sprintf(":%s 461 %s :Not enough params", s.name, s.upstreamLauncher.Self.Nick))
 	case errNoNick: