Calendar day view should start at 8am at the latest and hour of first event at the earliest.

Summary: Closes T8114, Calendar day view should start at 8am at the latest and hour of first event at the earliest.

Test Plan: Open day view on day with all day event and event at 5am, all day events should all be stacked at the top of the day view table, and day should start at 5am.

Reviewers: chad, #blessed_reviewers, epriestley

Reviewed By: #blessed_reviewers, epriestley

Subscribers: Korvin, epriestley

Maniphest Tasks: T8114

Differential Revision: https://secure.phabricator.com/D12779