bump stager
bump stager

[delivers #95934198]

Submodule src/github.com/cloudfoundry-incubator/stager 5684b43..61c688b:
  > Add debug logs for registry ips returned by consul

cloudfoundry-incubator/diego-release,cloudfoundry-incubator/diego-release,cloudfoundry-incubator/diego-release,cloudfoundry-incubator/diego-release