Instead, we make a proper registry class and house it within the main
window, then pass it to whatever needs access to the loaded hotkeys.
This way, we avoid a global variable, and don't need to initialize a
std::map instance before the program can do anything.
The hotkey widget has a separate class defined for it, and qt cannot automatically retranslate it when retranslateUi is called. This commit explicitly calls the function to retranslate the hotkey dialog.
