Added Object & Jigsaw Loot Tables

- Added the ability for placed objects and jigsaws to have select loot tables
    - Includes the ability to filter loot tables based on block type/block state
    - Overrides loot tables from the biome/region, but if no loot tables are provided for an object, they will still be used
    - Uses weight based system for determining which table to pick (so it's guaranteed rather than by chance)
- Added WeightedRandom util class
- Fixed loot tables not being random based on the seed
- Fixed jigsaws breaking bedrock
- Fixed enchantments in loot tables not working for enchanted books
- Fixed mobs spawned in Jigsaws not being spawned in the center like they should be

src/main/java/com/volmit/iris/util/WeightedRandom.java

@@ -0,0 +1,41 @@
+package com.volmit.iris.util;
+
+import java.util.Random;
+
+public class WeightedRandom<T> {
+
+    private KList<KeyPair<T, Integer>> weightedObjects = new KList<>();
+    private Random random;
+    private int totalWeight = 0;
+
+    public WeightedRandom(Random random) {
+        this.random = random;
+    }
+
+    public WeightedRandom() {
+        this.random = new Random();
+    }
+
+    public void put(T object, int weight) {
+        weightedObjects.add(new KeyPair<>(object, weight));
+        totalWeight += weight;
+    }
+
+    public T pullRandom() {
+        int pull = random.nextInt(totalWeight);
+        int index = 0;
+        while (pull > 0) {
+            pull -= weightedObjects.get(index).getV();
+            index++;
+        }
+        return weightedObjects.get(index).getK();
+    }
+
+    public int getSize() {
+        return weightedObjects.size();
+    }
+
+    public void shuffle() {
+        weightedObjects.shuffle(random);
+    }
+}