Bump src/cloud_controller_ng

Bump cloudfoundry/cloud_controller_ng:
  Joseph Palermo and Zach Robinson:
     Fix flaky specs ( Travis started: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/28919332 )
     Fix flaky spec ( Travis started: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/28918798 )
     Consolidate all Rspec.configure blocks into spec_helper ( Travis Failed: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/28918445 )
     remove unnecessary test ( Travis Failed: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/28915707 )
     Remove service_instances integration tests. ( Travis Success: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/28914827 )
  Joseph Palermo:
     Remove savepoint: true from code and specs now that auto_savepoint works ( Travis Success: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/28899127 )
     Upgrade Sequel ( Travis Unknown )