* dev:
Add translation files for all categories
Move the generic helpfiles into categories: generic, object, bots and cbot
Add translation files for all levels
Move help files to level-specific directories
Correct the Polish files capitalisation to be uniform across languages
Move level scenes to level-specific directories
Add the help/ and levels/ CMake machinery to enable the po-based translations
Add CMake-Po4a-based infrastructure to allow po-based translation of Colobot help- and scene-description (level) files
Conflicts:
levels/gen_levels_xml.sh