First stab at day view

Summary: Ref T4393, First stab at day view.

Test Plan: Open Calendar Advanced Search, select "Day View (beta)", see rough day view of selected day.

Reviewers: chad, epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: Korvin, epriestley

Maniphest Tasks: T4393

Differential Revision: https://secure.phabricator.com/D12685