implemented ISF scripts decryption.

ArcFormats/WidgetISF.xaml.cs

@@ -0,0 +1,17 @@
+using System.Windows.Controls;
+
+namespace GameRes.Formats.GUI
+{
+    /// <summary>
+    /// Interaction logic for WidgetISF.xaml
+    /// </summary>
+    public partial class WidgetISF : StackPanel
+    {
+        public WidgetISF ()
+        {
+            InitializeComponent ();
+            if (-1 == Scheme.SelectedIndex)
+                Scheme.SelectedIndex = 0;
+        }
+    }
+}