R1:a2588d62e7f6

Minor `bin/aphlict` cleanup

Summary: Ref T10697. This just improves a couple of minor `bin/aphlict` things: make argument parsing more explicit/consistent, consolidate a little bit of duplicated code.

Test Plan: Ran all `bin/aphlict` commands.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T10697

Differential Revision: https://secure.phabricator.com/D15698