Use new menu contsants in home menu item

Summary: Ref T11957, just lays in some minor bug fixes. Sets correct menu, removes sidebar on edit.

Test Plan: Test /menu/ on home with Admin and Normal accounts.

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: Korvin

Maniphest Tasks: T11957

Differential Revision: https://secure.phabricator.com/D17247