ui - textbox:
added default ctor
render:
added an std::map<T, E> overload
editor - settingsbar:
done the textboxes with a std::map
added level_background class
level_manager:
adapted to level_background
editor - settingsbar:
added textbox-text getters
editor - mouse:
added get_selectionshape_bounds
editor:
adapted to level_background
game_handler:
loading the background
mlk update