Send PART msg to channel for quitting users

server.go

@@ -130,9 +130,10 @@ func (sv *Server) dispatch() {
 		case cl := <-sv.DelClient:
 			nick := cl.Name()
 			cl.Destroy()
-			for _, ch := range sv.chUsers {
+			for chname, ch := range sv.chUsers {
 				if _, exists := ch[nick]; exists {
 					delete(ch, nick)
+					sv.sendMsg(irc.M(nick, "PART", chname, "quit"))
 				}
 			}
 			delete(sv.clients, nick)