some refactors + better id setting

src/main/java/net/hexa/MythicItems/MythicItems.java

@@ -0,0 +1,17 @@
+package net.hexa.MythicItems;
+import org.bukkit.plugin.java.JavaPlugin;
+
+
+public class MythicItems extends JavaPlugin {
+    @Override
+    public void onEnable() {
+        getLogger().info("onEnable is called!");
+        this.getCommand("essence").setExecutor(new CommandMythicEssence());
+        getServer().getPluginManager().registerEvents(new MythicListener(), this);
+    }
+
+    @Override
+    public void onDisable() {
+        getLogger().info("onDisable is called!");
+    }
+}