2.99.4: (unstable): * Remove use of Gtk::Application because it was removed from gtkmm 3.0. (Murray Cumming) * Builder section: Remove a now non-existent property. (Murray Cumming) * ComboBox section: Mention set_entry_text_column() instead of set_text_column(). (Kalev Lember) * Add basic information on Gtk::Grid. (David King) * Modify the custom_container and custom_widget examples. (Kjell Ahlstedt) * Replace gtkmm-2.24 mentions with gtkmm-3.0. (David King) * Build: Fix the installation path. (David King)