Issue 32: Objects added to the lifecycle after LifecycleManager.start() was called were getting
warmed up in the Guice thread. This could cause deadlocks and other problems. Further, each object
would get warmed up independently. I've reworked this code so that post-start warm ups occur in
a separate thread and there is a small padding period so that multiple objects added near the same
time can get warmed up together.