FIX:fixed download progress starting from 1%

Change-Id: I9b073e6fa1698f5ac02827d30e883f585ca68674

src/slic3r/GUI/Plater.cpp

@@ -8072,7 +8072,7 @@ void Plater::import_model_id(wxString download_info)
     wxString msg;
     wxString dlg_title = _L("Importing Model");
 
-    int percent = 1;
+    int percent = 0;
     ProgressDialog dlg(dlg_title,
         wxString(' ', 100) + "\n\n\n\n",
         100,    // range