R1:af6ffd8c7b34

Allow Almanac devices to have SSH keys

Summary: Ref T5833. Expose a key management interface for Almanac devices.

Test Plan: {F231962}

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T5833

Differential Revision: https://secure.phabricator.com/D10825