Add sandbox, phabricator, caching-proxy, production-rpc-servers, and domain-redirect to Alerta's resource map.
Add sandbox, phabricator, caching-proxy, production-rpc-servers, and domain-redirect to Alerta's resource map.

Test Plan: `tests/alertlib_test.py`

Reviewers: amos, drosile, jacqueline, csilvers

Reviewed By: amos

Differential Revision: https://phabricator.khanacademy.org/D40098

Khan/alertlib