Tweaked layout of SelectProductDialog.

- Tweaks to layout so that it resizes without artifacts.
- Removed parent window so that window manager will not center dialog on parent,
  which makes resizing difficult depending on size and location of parent window.

glabels/File.cpp

@@ -46,7 +46,7 @@ namespace glabels
 	///
 	bool File::newLabel( MainWindow *window )
 	{
-		SelectProductDialog dialog( window );
+		SelectProductDialog dialog;
 		dialog.exec();
 
 		const Template* tmplate = dialog.tmplate();