Addition of all Entity classes.

Each Entity creates a corresponding instance of a Craft Entity, to be
used whenever sending instances to an event handler with
getBukkitEntity().

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

@@ -2,6 +2,9 @@ package net.minecraft.server;
 
 import java.util.Random;
 
+import org.bukkit.craftbukkit.CraftServer;
+import org.bukkit.craftbukkit.entity.CraftSheep;
+
 public class EntitySheep extends EntityAnimals {
 
     public static final float a[][] = {
@@ -44,6 +47,10 @@ public class EntitySheep extends EntityAnimals {
         super(world);
         aP = "/mob/sheep.png";
         a(0.9F, 1.3F);
+        //CraftBukkit start
+        CraftServer server = ((WorldServer) this.l).getServer();
+        this.bukkitEntity = new CraftSheep(server, this);
+        //CraftBukkit end
     }
 
     protected void a() {