Reimplement sync for Neos 9

[mficzel]

After the initial release for Neos 9 the sync feature should be restored. Different to the old implementation it should configure explicitly which workspace / language should be translated to which workspace / language.

Possible config syntax could look like this:

Sitegeist:
  LostInTranslation:    
    nodeTranslation:
      synchronization:
           # en -> es
           - sourceWorkspaceName: live
              sourceLanguage: en
              targetWorkspaceName: es-review
              targetLanguage: es
           # en -> de 
           - sourceWorkspaceName: live
              sourceLanguage: en
              targetWorkspaceName: de-review
              targetLanguage: de

Also the new feature should probably work with a jobqueue as it will probably work onPublish and has to handle lots of events at once.