Changed live and dead methods to return immutable lists. changed the underlying datastructure to be a map as opposed to two list

src/main/java/com/google/code/gossip/GossipTimeoutTimer.java

@@ -14,10 +14,7 @@ import javax.management.timer.Timer;
  */
 public class GossipTimeoutTimer extends Timer {
 
-  /** The amount of time this timer waits before generating a wake-up event. */
   private long _sleepTime;
-
-  /** The gossip member this timer is for. */
   private LocalGossipMember _source;
 
   /**