Remove application callsites to "LiskDAO->loadOneRelative()"

Summary: Ref T13218. This is like loadOneWhere(...) but with more dark magic. Get rid of it.

Test Plan:

• Forced 20130219.commitsummarymig.php to hit this code and ran it with bin/storage upgrade --force --apply ....
• Ran 20130409.commitdrev.php with bin/storage upgrade --force --apply ....
• Called user.search to indirectly get primary email information.
• Did not test Releeph at all.

Reviewers: amckinley

Reviewed By: amckinley

Subscribers: PHID-OPKG-gm6ozazyms6q6i22gyam

Maniphest Tasks: T13218

Differential Revision: https://secure.phabricator.com/D19876