To prepare for translation support, this makes all of the widgets
cognizant of the language change event that occurs whenever
installTranslator() is called and automatically retranslates their text
where necessary.
This is important as calling the backing UI's retranslateUi() is often
not enough, particularly in cases where we add our own strings that
aren't controlled by it. In that case we need to manually refresh the
strings ourselves.
As the add-ons column takes the most processing time out of any (as it needs to search registration for updates/dlc, patch control NCAs, search for mods, etc.), an option was added to disable it. This does not affect the application of add-ons. In large game collections, this decreases game list refresh time by as much as 70%.
Given these are shown to the user, they should be translatable.
While we're at it, also set up the dialog to automatically retranslate
the dialog along with the combo boxes if it receives a LanguageChange
event.
Keeps the individual initialization of the combo boxes logically separate.
We also shouldn't be dumping this sort of thing in the constructor
directly.
