Zero Feature Release

Merge branch 'develop'

* develop:
  Added rep invariants and checkreps
  Added a failing test
  connect to firebase
  added comments to pickers and other clean up
  CreateEventActivity comments
  Fixed main page event display, restructured detail page, trying to get attendees to show as list
  comments on DetailActivity and MainActivity
  Detail activity skeleton
  create pages time and date pickers
  Create event xml