Bump src/cloud_controller_ng

Bump cloudfoundry/cloud_controller_ng:
  Matthew Sykes:
     Update API Docs checksum ( Travis created: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/26238385 )
     Correct api doc for positioning buidpacks ( Travis Unknown )
  Michael Fraenkel:
     Run specs without parallel_test on travis ( Travis started: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/26235959 )

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