Stop registering linked listeners twice

ModifyCommand and WorldEditRenderer registered themselves as listener although
the SpigotLinker already does, so all their event handlers ran twice.

LobbySystem/src/de/steamwar/lobby/command/ModifyCommand.java

@@ -25,7 +25,6 @@ import de.steamwar.lobby.LobbySystem;
 import de.steamwar.lobby.listener.PlayerSpawn;
 import de.steamwar.sql.SteamwarUser;
 import de.steamwar.sql.UserPerm;
-import org.bukkit.Bukkit;
 import org.bukkit.GameMode;
 import org.bukkit.entity.HumanEntity;
 import org.bukkit.entity.Player;
@@ -47,7 +46,6 @@ public class ModifyCommand extends SWCommand implements Listener {
 
     public ModifyCommand() {
         super("modify");
-        Bukkit.getPluginManager().registerEvents(this, LobbySystem.getInstance());
     }
 
     @Register

SpigotCore/SpigotCore_Main/src/de/steamwar/core/worldedit/WorldEditRenderer.java

@@ -55,7 +55,6 @@ public class WorldEditRenderer implements Listener {
     public WorldEditRenderer() {
         INSTANCE = this;
         we = WorldEditWrapper.getWorldEditPlugin();
-        Bukkit.getPluginManager().registerEvents(this, Core.getInstance());
 
         Bukkit.getScheduler().runTaskTimer(Core.getInstance(), () -> {
             for (Player player : Bukkit.getOnlinePlayers()) {