#928 add a placeholder for modifying schedule
#928 dispatch alert showing to main thread to avoid crash
#928 code refactoring, increase welcome message's time out from 2 to 3 seconds
#928 allow user editing schedule after joining an experiment
#928 fix a navigation bug
#928 code refactor
#928 adopting modern NS_ENUM macro
Merge pull request #939 from google/issue928

#928