Modernize Maniphest

Summary: Updates (some) of Maniphest for modern methods. Didn't convert Reports (probably need a setNavigation call added).

Test Plan: View List, edit task, new task, view reports.

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: Korvin

Differential Revision: https://secure.phabricator.com/D14597