Expose ccng.directories.diagnostics property

Enable specification of output directory for USR1 diagnostic files from
the cloud controller.
Merge remote-tracking branch 'origin/pr/383' into develop

Signed-off-by: Joseph Palermo <jpalermo@pivotallabs.com>
Bump src/cloud_controller_ng

Bump cloudfoundry/cloud_controller_ng:
  James Myers:
     Merge remote-tracking branch origin/pr/229 into HEAD ( Travis created: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/27148778 )
     Merge remote-tracking branch origin/pr/227 into HEAD ( Travis Unknown )
  Abhijit Hiremagalur:
     Default to sqlite when running focused spec outside of Rake ( Travis started: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/27146450 )
  Matthew Sykes:
     Avoid recreating tables too often ( Travis Success: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/26993185 )
     Test authz branches at ModelController only ( Travis Unknown )
     FakeApp is really a FrontController ( Travis Unknown )
     Ensure foreign keys for test models are Oracle friendly ( Travis Success: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/26985331 )
     Expose configuration for diagnostic output directory ( Travis Unknown )
     Collect basic diagnostics in response to USR1 ( Travis Unknown )
  Joseph Palermo:
     Merge remote-tracking branch origin/pr/231 ( Travis Success: https://travis-ci.org/cloudfoundry/cloud_controller_ng/builds/26990416 )
  fraenkel:
     Upload buildpack bits if they are missing in the blobstore ( Travis Unknown )

Signed-off-by: Joseph Palermo <jpalermo@pivotallabs.com>
Merge branch 'develop' of github.com:cloudfoundry/cf-release into develop