Declare common Lisk properties

Summary:
Calling ->setPHID() or other common Lisk setters creates an implicit public property $phid.
I don't like implicit properties and I see them as errors.
Its public visibility also makes me nervous and is vulnerable to bypassing any setters we may create.

Test Plan: Loaded homepage, checked log.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D3600