ACE-627 allow ordering of artifact data to be defined

- introduced an ArtifactDataHelper service that DeploymentProviders can use to
  define a particular order for the artifacts that are being returned by it.



git-svn-id: https://svn.apache.org/repos/asf/ace/trunk@1802921 13f79535-47bb-0310-9956-ffa450edef68