1. Fix the compatible of guava 18.
a. update the guava from 14.0.1 to 18.0 .
b. test the compatible of guava 1.4.1 and 1.8.
2. Add the NotificationHandler support.
a. Add the NotificationHandler register/unregister in LookupManager.
b. Add the notify for the NotificationHandler.
c. Change the NotificationHandler, add the serviceInstanceChange method.