Bump src/cloud_controller_ng

Bump cloudfoundry/cloud_controller_ng:
  Phan Le:
     Add test to ensure AppUsageEvents are created when destroying an org ( Travis started: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/15722414 )
     Test to verify destroying a space creates AppUsageEvents ( Travis Unknown )
Make pipefs directory of NFS server configurable

Ubuntu14.04 and Ubuntu12.04 have the `rpc_pipes` directory at
`/run/rpc_pipefs`.
Use `p()` for `nfs_server.idmapd_domain`