Move project icon editing into "Edit Details"

Summary: Ref T5482. Instead of editing icons and details seaparetly, use a bunch of Javascript to pop a dialog instead.

Test Plan: {F170528}

Reviewers: chad

Reviewed By: chad

Subscribers: epriestley

Maniphest Tasks: T5482

Differential Revision: https://secure.phabricator.com/D9743