Bump src/cloud_controller_ng

Bump cloudfoundry/cloud_controller_ng:
  James Myers:
     appease RuboCop: AssignmentInCondition ( Travis created: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/26231371 )
     diego staging completion handler handles failure ( Travis Failed: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/26176387 )
  Alex Stupakov and Leo Rossignac-Milon:
     Wrap a describe block around a test case that did not have one ( Travis Failed: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/26176951 )
     Pollution Detection option added to specs ( Travis Unknown )
  Alex Stupakov, Leo Rossignac-Milon and Zach Robinson:
     Change 3 polluting tests to non-transactional ( Travis Unknown )
  David Sabeti and Hristo Iliev:
     Added service guid in service plans response for unauthenticated users ( Travis Success: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/26144125 )
  David Sabeti:
     Implement unauthenticated logic for /v2/service_plans and /v2/services ( Travis Unknown )
  Leo Rossignac-Milon and Zach Robinson:
     Bump api version. ( Travis Success: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/25897588 )
     appease rubocop ( Travis Failed: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/25896070 )

Signed-off-by: Amit Gupta <agupta@pivotallabs.com>
Merge branch 'develop' of https://github.com/cloudfoundry/cf-release into develop