Programmatic access to health status

[obrunsmann]

Any interest of implementing something like

Health::isHealthy();

or

Health::getStatus('external_api');

Could be useful for 2 cases:

1. Showing a small badge on the main page (healthy/having issues) or adding a hint when downgrades expected.
2. Could check the status before hitting external services

[freekmurze]

Yup, that could be nice. Feel free to send a PR. Make sure to include tests and updated docs. 👍