Check calendar is installed on profile

Summary: Fixes T6199, checks if Calendar is installed and displays if so.

Test Plan: Turned Calendar on and off, tested both layouts.

Reviewers: btrahan, epriestley

Reviewed By: epriestley

Subscribers: epriestley, Korvin

Maniphest Tasks: T6199

Differential Revision: https://secure.phabricator.com/D10574