Add basic Datapack API

Co-authored-by: Jake Potrebic <jake.m.potrebic@gmail.com>

paper-api/src/main/java/org/bukkit/entity/EntityType.java

@@ -485,6 +485,7 @@ public enum EntityType implements Keyed, Translatable, net.kyori.adventure.trans
      * @param world the world to check
      * @return true if this EntityType can be used to spawn an Entity for this World.
      */
+    @Deprecated(forRemoval = true, since = "1.20") // Paper
     public boolean isEnabledByFeature(@NotNull World world) {
         return Bukkit.getDataPackManager().isEnabledByFeature(this, world);
     }