Merge pull request #11515 from gaye/bug-904830

Bug 904830 - Depend on marionette js helper in gaia a=test-only
Bug 903220 - Write a marionette test for creating a calendar event a=test-only r=lightsofapollo
Refactor calendar marionette work
Refactor calendar marionette work more
Refactor calendar marionette work even more
Refactor calendar marionette work even more
Small cleanup
Click on the event once we create it
Add code to scrape event data from ViewEvent view and fix bug in DateHelper that caused time based flakes
Use marionette helper plugin