The transport-helper did not give transport options such as
verbosity, progress, cloning, etc. to import and export based
helpers, like it did for fetch and push based helpers, robbing them
the chance to honor the wish of the end-users better.

* mh/transport-capabilities:
  transport-helper: ask the helper to set the same options for import as for fetch
  transport-helper: ask the helper to set progress and verbosity options after asking for its capabilities