improve SFF viewer

Author: swharden

dev/sff/SffViewer/Form1.Designer.cs

@@ -57,6 +57,7 @@ private void Form1_DragDrop(object sender, DragEventArgs e)
             {
                 if (path.EndsWith(".sff", StringComparison.OrdinalIgnoreCase))
                 {
+                    lblFileName.Text = System.IO.Path.GetFileName(path);
                     LoadSFF(path);
                     return;
                 }