Fix Massive Memory Leak

Pathfinder objects are storing references to ChunkCache's, and never cleaning up.

These ChunkCache's then leak other entity objects. Those entity objects then have leaks to their
own chunk cache. A recursive problem....

Clean up the ChunkCache reference after it is done being used.

Spigot-Server-Patches/Fix-Massive-Memory-Leak.patch

@@ -0,0 +1,26 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Aikar <aikar@aikar.co>
+Date: Thu, 31 Mar 2016 19:06:47 -0400
+Subject: [PATCH] Fix Massive Memory Leak
+
+Pathfinder objects are storing references to ChunkCache's, and never cleaning up.
+
+These ChunkCache's then leak other entity objects. Those entity objects then have leaks to their
+own chunk cache. A recursive problem....
+
+Clean up the ChunkCache reference after it is done being used.
+
+diff --git a/src/main/java/net/minecraft/server/PathfinderAbstract.java b/src/main/java/net/minecraft/server/PathfinderAbstract.java
+index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
+--- a/src/main/java/net/minecraft/server/PathfinderAbstract.java
++++ b/src/main/java/net/minecraft/server/PathfinderAbstract.java
+@@ -0,0 +0,0 @@ public abstract class PathfinderAbstract {
+         this.f = MathHelper.d(entityinsentient.width + 1.0F);
+     }
+ 
+-    public void a() {}
++    public void a() {this.a = (IBlockAccess) null;} // Paper - Fix massive memory leak. Intentionally casting to ensure compile error if obfuscation changes
+ 
+     protected PathPoint a(int i, int j, int k) {
+         int l = PathPoint.b(i, j, k);
+--

importmcdev.sh

@@ -54,6 +54,7 @@ import PacketPlayInResourcePackStatus
 import PacketPlayOutPlayerListHeaderFooter
 import PacketPlayOutTitle
 import PacketPlayOutUpdateTime
+import PathfinderAbstract
 import PathfinderGoalFloat
 import PersistentVillage
 import TileEntityEnderChest