Remove unneeded dateutils import in datecombo and added default display value

src/contents/ui/DateCombo.qml

@@ -5,7 +5,6 @@ import QtQuick 2.15
 import QtQuick.Controls 2.15 as QQC2
 import QtQuick.Layouts 1.15
 import org.kde.kirigami 2.15 as Kirigami
-import "dateutils.js" as DateUtils
 
 QQC2.ComboBox {
     id: root
@@ -13,7 +12,7 @@ QQC2.ComboBox {
     signal newDateChosen(int day, int month, int year)
 
     property int timeZoneOffset: 0
-    property string display
+    property string display: dateTime.toLocaleString(Qt.locale(), Locale.NarrowFormat) // Can override for better C++ time strings
     property date dateTime: new Date()
     property date dateFromText: Date.fromLocaleDateString(Qt.locale(), editText, Locale.NarrowFormat)
     property bool validDate: !isNaN(dateFromText.getTime())