Read a GPX file then extract longitude and latitude values.
A GPX file for test is from https://github.com/gps-touring/sample-gpx/blob/master/BrittanyJura/Alt_Portsmouth.gpx
Read a GPX file then extract longitude and latitude values.
A GPX file for test is from https://github.com/gps-touring/sample-gpx/blob/master/BrittanyJura/Alt_Portsmouth.gpx