Have a health checker object, which assembles the result of health checks
Add the store and scheduler to the health checker object
Pass the health check function to the rest endpoint
Change the store health check to return (bool, details) as the scheduler health check does
Actually pass the health check function to the otter rest api
Lint fixes
Fix api service-making test
Make the health checker just take callables
Use gatherResults instead of DeferredList since we catch all failures as unhealthy - thanks @manishtomar
Fix copy-pasted docstrings - thanks @manishtomar
A positive health check test, thanks @manishtomar
Merge pull request #538 from rackerlabs/auto-862-combined-health-check

Auto 862 combined health check