[FEATURE] Display multiple gpx files

[lentemoore]

It would be really great if osmin wouldn't remove all but the last selected gpx file from the map view. Sometimes I follow one track until it intersects with the next, or need another track as a reference.

[janbar]

As track colors are limited (GPẌ standard from Garmin), only the current recorded track (dark green color) and tracks from the selected GPX file are displayed. Your GPX can contain few tracks. So you can merge them in one GPX file, using QMapShake or the Garmin app.

[janbar]

I tried before to load more than one GPX, but it was a mess when tracks with the same color cross themselves.
We can re-enable the feature and add a new menu item to disable activated tracks when we want to cleanup: todo ...