R1:97a4a59cf2c7

Give the Phortune external portal an order view

Summary:
Depends on D20739. Ref T13366. Slightly modularize/update components of order views, and make orders viewable from either an account context (existing view) or an external context (new view).

The new view is generally simpler so this mostly just reorganizes existing code.

Test Plan: Viewed orders as an account owner and an external user.

Maniphest Tasks: T13366

Differential Revision: https://secure.phabricator.com/D20740