Add translations

[tlahmann]

All strings should be translated

[spmse]

We need translation templates for:

• italian add italian language template #36
• french Add french language template. #40 (done by @clabroche 🎉 )
• spanisch add spanish language template  #38
• turkish add turkish language template  #39 (currently WIP by @erso44 )

Feel free to create a new issue with a proposal for a new language template that should be included to kuro. The issue will be added to this list and linked.