Bump src/cloud_controller_ng

Bump cloudfoundry/cloud_controller_ng:
  James Myers:
     User visibility for app security groups ( Travis created: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/27339738 )
     Remove unused creation_req and update_req code from controller specs ( Travis Success: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/27328463 )

Signed-off-by: Joseph Palermo <jpalermo@pivotallabs.com>