Support Spaces in Pholio

Summary:
Ref T8493. Add Spaces support to Pholio.

This is straightforward; Pholio has no clone/copy/fork or weird parent/child stuff going on.

Test Plan: Created a mock, put it in a space, looked at it as another user, searched for stuff in spaces, viewed Macros.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T8493

Differential Revision: https://secure.phabricator.com/D13231