Remove some dead comments

core/src/main/scala/spark/CacheTracker.scala

@@ -204,17 +204,11 @@ private[spark] class CacheTracker(actorSystem: ActorSystem, isMaster: Boolean, b
         }
         try {
           // If we got here, we have to load the split
-          // Tell the master that we're doing so
-          //val host = System.getProperty("spark.hostname", Utils.localHostName)
-          //val future = trackerActor !! AddedToCache(rdd.id, split.index, host)
-          // TODO: fetch any remote copy of the split that may be available
-          // TODO: also register a listener for when it unloads
           val elements = new ArrayBuffer[Any]
           logInfo("Computing partition " + split)
           elements ++= rdd.compute(split, context)
           // Try to put this block in the blockManager
           blockManager.put(key, elements, storageLevel, true)
-          //future.apply() // Wait for the reply from the cache tracker
           return elements.iterator.asInstanceOf[Iterator[T]]
         } finally {
           loading.synchronized {