Update KSpigot to 1.18.1

src/main/kotlin/net/axay/kspigot/data/NBTDataLoader.kt

@@ -0,0 +1,27 @@
+package net.axay.kspigot.data
+
+import net.axay.kspigot.annotations.NMS_General
+import net.minecraft.nbt.CompoundTag
+import org.bukkit.craftbukkit.v1_18_R1.entity.CraftEntity
+import org.bukkit.craftbukkit.v1_18_R1.inventory.CraftItemStack
+import org.bukkit.entity.Entity
+import org.bukkit.inventory.ItemStack
+
+@NMS_General
+var Entity.nbtData: CompoundTag
+    get() {
+        val nbtTagCompound = CompoundTag()
+        (this as CraftEntity).handle.save(nbtTagCompound)
+        return nbtTagCompound
+    }
+    set(value) {
+        (this as CraftEntity).handle.load(value)
+    }
+
+@NMS_General
+val ItemStack.nbtData: CompoundTag
+    get() {
+        CraftItemStack.asNMSCopy(this).let {
+            return if (it.hasTag()) (it.tag ?: CompoundTag()) else CompoundTag()
+        }
+    }