#675 remove legacy code. The generated esm schedules are stored inside instance plist, and the definition schedule is copied to experiment, not retained and then modified any more
#675 code refactoring, add some logs
#675 fix the bug that scheduling new notifications will clear fired but not time out notifications from the notification center
#675 : add a joinDate to PacoExperiment so that we can use it to calculate the on-going schedules
#675 use experiment join date midnight as the starting point of calculating schedules for on-going experiments, so that we can keep consistently generating dates using repeatRate and start date
#675 code refactoring
Merge pull request #695 from google/issue675

Issue675