Rethink language setting

[michal-josef-spacek]

When I do:

• Run app
• Set language to English
• Exit (save to settings.vicuna)
• Run app again (is in English)
• Load images
• Save to session (in session.xml will be lang=en)
• Run app
• Set language to Czech
• Exit (save to settings.vicuna)
• Run app again (is in Czech)
• Load session (load lang=cz in situation when lang is en) This mean, some texts are in Czech.
• Save (save Czech to settings.vicuna)