Add slime world support for per player worlds

Move package to dev.plex.extras to prevent any possible conflicts with main plugin

src/main/java/dev/plex/extras/command/EnglishMfCommand.java

@@ -0,0 +1,48 @@
+package dev.plex.extras.command;
+
+import dev.plex.command.PlexCommand;
+import dev.plex.command.annotation.CommandParameters;
+import dev.plex.command.annotation.CommandPermissions;
+import dev.plex.rank.enums.Rank;
+import dev.plex.util.PlexUtils;
+import net.kyori.adventure.text.Component;
+import org.bukkit.Bukkit;
+import org.bukkit.command.CommandSender;
+import org.bukkit.entity.HumanEntity;
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.List;
+import java.util.stream.Collectors;
+
+/**
+ * Credit to AcidicCyanide <3
+ * Credit to "TheDeus-Group" for the messages :)
+ */
+
+@CommandParameters(name = "emf", description = "Speak english.", usage = "/<command> <player>")
+@CommandPermissions(level = Rank.ADMIN, permission = "plex.tfmextras.emf")
+public class EnglishMfCommand extends PlexCommand
+{
+    @Override
+    protected Component execute(@NotNull CommandSender sender, @Nullable Player player, @NotNull String[] args)
+    {
+        if (args.length == 0)
+        {
+            return usage();
+        }
+        Player target = getNonNullPlayer(args[0]);
+        target.sendMessage(mmString("<red>ENGLISH MOTHERFUCKER, Do you speak it!?"));
+        PlexUtils.broadcast("<red>" + sender.getName() + " is sick of " + target.getName() + " not speaking English!");
+        target.setHealth(0);
+        target.getWorld().strikeLightningEffect(target.getLocation());
+        return null;
+    }
+
+    @Override
+    public @NotNull List<String> tabComplete(@NotNull CommandSender sender, @NotNull String alias, @NotNull String[] args) throws IllegalArgumentException
+    {
+        return Bukkit.getOnlinePlayers().stream().map(HumanEntity::getName).collect(Collectors.toList());
+    }
+}