Fix the Import / Export Guides

The import / export guides have a lot of repeated, extraneous material. The conceptual information should all be in the top level page. The rest of the pages need to be slimmed down.

Furthermore, the pages need to be made more symmetrical across Server and Capella. For instance, on the Capella side, the import and export with the command line page shows how to generate cbimport / cbexport code, not actually how to use these command line tools. There is similar functionality on the Server side, which is not explained. Finally, there is no actual export procedure on the Server side.