Replaced Gtk ComboBoxes with custom one https://github.com/KanoComputing/kano-settings/issues/39
Added checks for KanoComboBox getters
Reviewed getter checks https://github.com/KanoComputing/kano-settings/pull/167
Merge pull request #167 from KanoComputing/combobox-replacement

Replaced Gtk ComboBoxes with custom one https://github.com/KanoComputing...