Moved logic from ListenResource to SystemManager. Moved some /update endpoints to /system. Added health check
Moved SpawnBalancerConfig handling to SpawnBalancer. Deleted SpawnBalancerConfig from SpawnState
Moved quiesce logic out of Settings
Only log quiesce message if state changed
Moved more stuff from spawn to other classes
Some cleaning up
Merge pull request #125 from addthis/healthcheck-n-system-manager

Healthcheck and system manager refactoring