Connect from commandline (#3556)

* - Use Qt argument parser
- Add --connect command line option.

* Better version info

cockatrice/src/window_main.h

@@ -137,9 +137,14 @@ private:
     DlgConnect *dlgConnect;
     GameReplay *replay;
     DlgTipOfTheDay *tip;
+    QUrl connectTo;
 
 public:
     explicit MainWindow(QWidget *parent = nullptr);
+    void setConnectTo(QString url)
+    {
+        connectTo = QUrl(QString("cockatrice://%1").arg(url));
+    }
     ~MainWindow() override;
 
 protected: