Drive conduit result ordering through Query order specifications

Summary:
Ref T7803. Ref T5873. Allows Query methods to expose orderings from the underlying Query class nearly-for-free.

Callers can specify a string to use a builtin ordering, or an array to use a low-level column ordering.

Test Plan:

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T5873, T7803

Differential Revision: https://secure.phabricator.com/D12381