adding successors field to instance
adding successor selection and supporting test to instance creation
adding prepare successor request messages
adding successor serialization to the instance serialization
adding method to handle prepare successor requests
adding stubbed successor prepare tests
adding empty successor list to instance setup function
fixing prepare proceed locking logic (hack, left todo)
beginning work on defer prepare method
adding event struct, which wraps the sync.Cond logic
adding instance locks, and commit/execute events and getters
adding some comments around lock and event members
replacing commit notify with commit event
fixing prepare commit notify wait
splitting wait into wait and getchan
replacing executeNotify with executeEvent
updating test logging to off
making some test timeouts very short
switching to instance level prepare lock
implementing prepare message serialization and tests