added some missing comments for falling entities

src/main/java/net/minecraft/server/BlockSand.java

@@ -27,6 +27,7 @@ public class BlockSand extends Block {
             byte b0 = 32;
 
             if (!instaFall && world.a(i - b0, j - b0, k - b0, i + b0, j + b0, k + b0)) {
+                // CraftBukkit Change call to add data
                 EntityFallingSand entityfallingsand = new EntityFallingSand(world, (double) ((float) i + 0.5F), (double) ((float) j + 0.5F), (double) ((float) k + 0.5F), this.id, world.getData(i, j, k));
 
                 world.addEntity(entityfallingsand);

src/main/java/net/minecraft/server/EntityFallingSand.java

@@ -14,7 +14,7 @@ public class EntityFallingSand extends Entity {
     public EntityFallingSand(World world, double d0, double d1, double d2, int i, int data) {
         super(world);
         this.a = i;
-        this.data = data;
+        this.data = data; // CraftBukkit
         this.aY = true;
         this.b(0.98F, 0.98F);
         this.height = this.width / 2.0F;