Revert "Bump src/cloud_controller_ng"

This reverts commit 8b02a778a862653b556988fc9740924994dfaf45.
Bump src/cloud_controller_ng

Bump cloudfoundry/cloud_controller_ng:
  Abhijit Hiremagalur:
     CC fails to stage if app wants Diego and Diego is disabled ( Travis created: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/32031041 )
     InstancesReporter is Diego based if app wants it ( Travis Unknown )
     Centralize knowledge of Diego env vars ( Travis Unknown )
     Make diego client send_stage_request match docker client ( Travis Unknown )
     Introduce Diego::Docker::Client ( Travis Unknown )
  Derek Richard and Raina Masand:
     Updated error message on failed create of service_instance with no name ( Travis started: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/32030663 )

Signed-off-by: Stewart Nickolas <nickolas@us.ibm.com>