Handle *nix/windows paths in gui version
Don't consider files with the string endomondo in the filename.
Handle manual added (empty workouts)

Handle empty workouts from Sports Tracker
The trk section looks like this:
  <metadata>
    <name>Other1 18/03/2009/04:28:00</name>
    <desc></desc>
    <author>
      <name>Aske Olsson</name>
    </author>
    <link href="www.sports-tracker.com">
      <text>Sports Tracker</text>
    </link>
  </metadata>
  <trk>
    <trkseg/>
  </trk>
Split output file to serveral files of 10MB hunks