WIP: Start adding some Occidental (Interlingue) translations

[Dhghomon]

WIP: Adding some Occidental (Interlingue) translations of the interface. Will remove WIP when ready to merge.

[buhtz]

Hello Dave,
On behalf of the team, thank you for your contribution and taking the time to improve Back In Time. We appreciate it.

Would you mind provide your translations via our Weblate platform instead of modifying the po file directly. po files in the repo are usually overwritten by the ones form the Weblate platform. See #1915 for details how to register and login to Weblate.

https://translate.codeberg.org/projects/backintime/common/ie/

EDIT: If you want I can save your work on the po file and you don't need to re-do it on Weblate. But I need to lock the weblate project for this. Let me know how you want to proceed: 1) Re-do the work on weblate or 2) wait some hours until I integrated your po-file into the project and weblate and you can proceed further on weblate after this.

[Dhghomon]

@buhtz Ah, looks similar to Crowdin! Thanks, I'll do the translation there then. Don't worry about locking Weblate, the existing work won't take more than a few minutes for me to redo.