anchor.diff:  layout:: Map layout to use (default: "plain")
   style:: Map base style to use (default: "CartoOSM")
   overlays:: List of overlays to put on top of base style (default: None)
  -paper_size:: Paper size to use (default: "Din A4" 210x297mm²)
  -orientation:: Paper orientation: "portrait" or "landscape" (default: "portrait")
  -track_url:: URL pointing to a GPX track to download and print
  -umap_url:: URL pointing to an Umap export file do download and print
  -
  -It is also possible to upload GPX and Umap files directly using a multipart/form-data
  -POST request. In this case you have to submit the actual API JSON as a post parameter
  -named "json", and add file fields named "track" for a GPX track, or "umap" for an
  -Umap JSON export.
  +paper_height:: Paper height in mm
  +paper_width:: Paper width in mm
  +paper_size:: Predefined paper size to use (default: "Din A4" 210x297mm²)
  +orientation:: Paper orientation: "portrait" or "landscape" when using a predefined paper size (default: "portrait")
  +import_url:: URL pointing to an import file in one of the supported formats
  +track_url:: URL pointing to a GPX track to download and print (deprecated)
  +umap_url:: URL pointing to an Umap export file do download and print (deprecated)
  +
  +It is also possible import files directly using a multipart/form-data POST request.
  +In this case you have to submit the actual API JSON as a post parameter
  +named "json", and add file fields using whatever field name you like.
  +
  +Supported import file formats for now are GPX tracks, Umap map exports, and POI
  +files as generated by the "Umgebungsplaene" neighborhood POI web application.
   
   After successfully submitting a request you can either poll the job result API every
   once in a while until it either returns the "200 OK" status, or a 4xx error code.
  
positive.code:     </trkseg>
    </trk>
  </gpx>
  --XXXXXXXX--
  ----
  
  
negative.code:     "paper_size": "Din A1"
  }
  --XXXXXXXX
  Content-Disposition: form-data; name="file1"; filename="test.gpx"
  Content-Type: application/gpx+xml
  
  <?xml version="1.0" encoding="UTF-8"?>
  