Modernize Calendar View

Summary: Updates Calendar View to more modern components.

Test Plan: Browse Calendar Forward and Back, Create a Status, Get Excited, Get PUMPED.

Reviewers: epriestley, btrahan

Reviewed By: epriestley

CC: Korvin, epriestley, aran

Maniphest Tasks: T4392

Differential Revision: https://secure.phabricator.com/D8247