Bump src/cloud_controller_ng

Bump cloudfoundry/cloud_controller_ng:
  Matthew Horan and alex choi:
     Revert "Revert "[finishes #56091544] service deprovision should give user an error when it fails"" ( Travis Success: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/11831278 )
     Revert "Revert "Raise error when unbind fails on broker"" ( Travis Unknown )
  Cornelia Davis and Matthew Horan:
     Nest types and backtrace for V2 broker errors within error hash ( Travis Success: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/11802140 )
     Include types and backtrace for internal errors ( Travis Unknown )
     Bump vcap-common ( Travis Unknown )
     Bump vcap_common ( Travis Success: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/11758213 )
     Rename StructuredError#source to #error ( Travis Unknown )
     Consolidate testing of broker error propagation ( Travis Unknown )
     Rename service broker registration to managedment ( Travis Unknown )
  Julz Friedman and Ruth Byers:
     Adds a rescue for EISDIR errors deleting droplets ( Travis Success: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/11786267 )
  Julz Friedman and Mark Rushakoff:
     Fix issue with requiring delayed job before migrations occur ( Travis Unknown )
  Mark Rushakoff and Ruth Byers:
     WIP: Use Sequel Delayed Job plugin ( Travis Unknown )
  phanle:
     Removed mutex ( Travis Success: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/11761514 )
  Maria Shaldibina and Phan Le:
     Refactor droplets URL generation ( Travis Success: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/11753910 )
     Allow any user with right basic auth credentials to download builbpacks. It used to only allow admin to download. Also allow to skip authentication on per operation basis. ( Travis Unknown )
     Move logic of URL generations out of StagingsController. ( Travis Unknown )
     Clarify blobstore methods ( Travis Unknown )
     Remove in memory state in CC when DEA uploads droplets and buildpack cache. ( Travis Unknown )
  Alex Suraci and Phan Le:
     Gradually killing DSL magics. ( Travis Unknown )
     an app is staged when its droplet is uploaded ( Travis Unknown )