Only check for file association once (Win32)

Magnet link association (Win32)

src/GUI.cpp

@@ -218,11 +218,13 @@ GUI::GUI(QWidget *parent, QStringList torrentCmdLine) : QMainWindow(parent), dis
 
   qDebug("GUI Built");
 #ifdef Q_WS_WIN
-  if(!Preferences::isFileAssocOk()) {
+  if(!Preferences::neverCheckFileAssoc() && !Preferences::isFileAssocOk()) {
       if(QMessageBox::question(0, tr("Torrent file association"),
-                               tr("qBittorrent is not the default application to open torrent files.\nDo you want to associate qBittorrent to torrent files?"),
+                               tr("qBittorrent is not the default application to open torrent files or Magnet links.\nDo you want to associate qBittorrent to torrent files and Magnet links?"),
                                QMessageBox::Yes|QMessageBox::No, QMessageBox::Yes) == QMessageBox::Yes) {
           Preferences::setFileAssoc();
+      } else {
+          Preferences::setNeverCheckFileAssoc();
       }
   }
 #endif