NEWS: Mention API Additions since 2.42
NEWS: Mention API Additions since 2.42

GNOME/glibmm,GNOME/glibmm,johne53/MB3Glibmm,GNOME/glibmm,GNOME/glibmm,johne53/MB3Glibmm,johne53/MB3Glibmm,GNOME/glibmm,johne53/MB3Glibmm