Introduce buffering in HashChunkletManager

Improve the performance by introducing buffering. The current usage of FileInputStream and ObjectInputStream don't use buffering.

src/main/java/com/gmail/nossr50/util/blockmeta/HashChunkletManager.java

@@ -346,7 +346,7 @@ public class HashChunkletManager implements ChunkletManager {
 
         try {
             fileIn = new FileInputStream(location);
-            objIn = new ObjectInputStream(fileIn);
+            objIn = new ObjectInputStream(new BufferedInputStream(fileIn));
             storeIn = (ChunkletStore) objIn.readObject();
         }
         catch (IOException ex) {