R1:52d563f8b8cf

Make differential.querydiffs more liberal about arguments

Summary:
Fixes T12092. D17164 made `DiffQuery` more strict about arguments using modern conventions, but `differential.querydiffs` uses bizarre ancient conventions.

Give it more modern conventions instead.

Test Plan: Made a `querydiffs` call with only revision IDs.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T12092

Differential Revision: https://secure.phabricator.com/D17172