Adding the Conduit query method.

Summary:
T2154
Adding the Conduit query method implementation, and metadata to the phutil register library.

Test Plan:
Choose conduit.query on the web UI to see information about the method.
Then, click the "Call Method" button and observe the method result.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D4550