flash message can be more than one word

src/engine/devcmd/cmds/FlashMsgCmd.java

@@ -30,7 +30,7 @@ public class FlashMsgCmd extends AbstractDevCmd {
             this.sendUsage(pcSender);
             return;
         }
-        ChatManager.chatSystemFlash(args[0]);
+        ChatManager.chatSystemFlash(String.join(" ", args));
     }
 
     /**