Summary: Ref T7986, Ability to invite users, but not RSVP yet. Test Plan: Open event, add invitees, save, event detail view should show invitees. Reviewers: #blessed_reviewers, epriestley Reviewed By: #blessed_reviewers, epriestley Subscribers: Korvin, epriestley Maniphest Tasks: T7986 Differential Revision: https://secure.phabricator.com/D12617