Moderize Herald UI

Summary: Removes many tables and uses PropertyLists and ObjectItemList when possible. Adds cleaner CSS, makes mobile editing more possible.

Test Plan: Test new UI on desktop and mobile. Verify all functionality still exists.

Reviewers: btrahan, epriestley

Reviewed By: epriestley

Subscribers: epriestley, Korvin

Maniphest Tasks: T4272

Differential Revision: https://secure.phabricator.com/D8860