add a method to toggle a content group of given kind for all preferred languages
add a method to toggle a content group of given kind for all preferred languages

josve05a/wikipedia-ios,josve05a/wikipedia-ios,julienbodet/wikipedia-ios,wikimedia/apps-ios-wikipedia,wikimedia/wikipedia-ios,wikimedia/wikipedia-ios,montehurd/apps-ios-wikipedia,wikimedia/apps-ios-wikipedia,julienbodet/wikipedia-ios,wikimedia/apps-ios-wikipedia,josve05a/wikipedia-ios,wikimedia/wikipedia-ios,wikimedia/wikipedia-ios,wikimedia/apps-ios-wikipedia,julienbodet/wikipedia-ios,josve05a/wikipedia-ios,wikimedia/wikipedia-ios,josve05a/wikipedia-ios,montehurd/apps-ios-wikipedia,julienbodet/wikipedia-ios,wikimedia/apps-ios-wikipedia,montehurd/apps-ios-wikipedia,wikimedia/apps-ios-wikipedia,julienbodet/wikipedia-ios,julienbodet/wikipedia-ios,josve05a/wikipedia-ios,julienbodet/wikipedia-ios,montehurd/apps-ios-wikipedia,julienbodet/wikipedia-ios,montehurd/apps-ios-wikipedia,wikimedia/wikipedia-ios,wikimedia/apps-ios-wikipedia,josve05a/wikipedia-ios,wikimedia/apps-ios-wikipedia,wikimedia/wikipedia-ios,montehurd/apps-ios-wikipedia,montehurd/apps-ios-wikipedia,montehurd/apps-ios-wikipedia,josve05a/wikipedia-ios