Normalize headers and actions in Project sub pages

Summary: Run through all the pages in projects and make sure they all feel similar. Adds back curtain on board manage page, even though it is sad for only having a single action.

Test Plan: Test all pages on a project for consistency in UI.

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: Korvin

Differential Revision: https://secure.phabricator.com/D17909