Added a stop command

I found the absence of a stop command particuraly annoying so i implemented it in 10 minutes

README.md

@@ -80,6 +80,7 @@ Server commands can be run in the server console or in-game. There is a dummy us
 /reload. Reloads the server config.
 /scene [scene id] [floor id]. Teleports the player to the specified scene.
 /spawn [monster/prop id] x[amount] s[stage id]. Spawns a monster or prop near the targeted player.
+/stop. Stops the server
 /unstuck @[player id]. Unstucks an offline player if they're in a scene that doesn't load.
 /worldlevel [world level]. Sets the targeted player's equilibrium level.
 ```

src/main/java/emu/lunarcore/command/commands/StopCommand.java

@@ -0,0 +1,20 @@
+package emu.lunarcore.command.commands;
+
+
+import emu.lunarcore.command.Command;
+import emu.lunarcore.command.CommandArgs;
+import emu.lunarcore.command.CommandHandler;
+
+@Command(label = "stop",
+    aliases = {"exit"},
+    permission = "admin.stop",
+    requireTarget = false,
+    desc = "/stop - Stops the server")
+public class StopCommand implements CommandHandler {
+
+    @Override
+    public void execute(CommandArgs args) {
+        args.sendMessage("Stopping server");
+        System.exit(1000);
+    }
+}