Translation

The existing translation pull request didn't cover a lot of missing translation parts. This pull requests aims to completely translate the workshoppers.

Plan:
- [x] Integrate translation system that can be applied to every string shown to the people
- [x] Add test files for another translation system
- [x] Fixed menu system 
- [ ] Add translation selector & command line arguments to the workshopper
- [ ] Add a fallback in case a language of a workshop is not covered by the workshopper general module
- [ ] Update the workshopper-exercise system
- [ ] Test every case where output is desired and see if it still works
- [ ] Improve the feedback in case translation is missing