#645: remove events from PacoExperiment
#645 : code refactoring
#645 : refactor PacoEditScheduleViewController
#645: refactor PacoScheduleEditView
#645: store edited schedule inside experiment instance plist
#651 : add a log for modified schedule when joining
#651 : fix the payload of schedule
#651 : code refactoring
#646 add PacoTimeEditView for esm start and end time editing
#646 enable start time and end time editing for esm schedule when user joins an experiment
#646 add time evaluation
#646 remove definition from PacoScheduleEditView
#646 change the random number generating algorithm to generate fixed numbers instead of random numbers when the duration and numOfIntegers violate minimum buffer.
#647 enable editing times for daily experiment
#647  fix a crash
#647 sort times and detect duplicate times after user finishes editing times for daily experiment
#647 code refactor, evaluate schedule before user clicks on Join button
#647 only generate one date if the duration is less than the minimum buffer
#646 clear esm schedule list stored inside the definition when user stops an experiment
#647 code refactor