Integrate the Arabic Localisation of JSesh

[rosmord]

I'd like to integrate the localisation proposed by our colleague Hany ZARIF. However, some part of it don't work very well with the Swing library, especially changing the whole application layout from left-to-right to right-to-left.

As a consequence, I think a temporary version, with a partial localisation (localised menus and texts, but keeping the general layout) would be a solution. As it's not a perfect solution, some colleagues may prefer to be able to choose which version they use.

https://jsesh.qenherkhopeshef.org/news/news20240304

So:

• add a way to choose one of the available localisations;
• integrate the arabic localisation, which entails changing a few screens to have a coherent arabic text.