Make Calendar day view a little more consistent

Summary: Ref T11326. This just cleans things up a little and removes some of the obvious layout/CSS issues.

Test Plan:

• Viewed day view before/after. Also viewed profile panel.

Before:

{F1725547}

After:

{F1725548}

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T11326

Differential Revision: https://secure.phabricator.com/D16308