Integration test all lifecycle event types

[jwreagor]

I'm not seeing an integration test that exercises all possible lifecycle event types that we mention in our documentation. We should have a test or tests that showcase desired behavior of things such as...

• enterMaintenance
• exitFailed
• exitMaintenance
• shutdown
• startup
• stopped
• unhealthy

Existing tests exercise the following.

• test_discovery_consul: exitSuccess, changed
• test_envvars: healthy
• test_sighup: signal events SIGHUP and SIGUSR2
• test_sigterm: stopping

I'm ok with redundancy if the tests are scattered across multiple test cases AND ALSO qualified within a single test (if that's possible).