Feature request - support for long files

[ShikOfTheRa]

Most of my flights are > 10 minutes so files are split.

Is it feasible to add support for "joining" of files.

I have produced separate files and tried to join using apps, but they have not been very successful. Usually errors playing.

[odgrace]

I have it working with the CLI in a draft PR. Will need a bit of review and polishing

#50

[ShikOfTheRa]

That is awesome. Look forward to inclusion.

Thank you both for your time and effort.

Happy to do any testing..