Change dialogs to use Qt's version.

The native dialogs have different behavior when dealing with
filters. Qt's behavior is well defined.

src/SeerConsoleWidget.cpp

@@ -137,6 +137,7 @@ void SeerConsoleWidget::handleSaveButton () {
     */
 
     QFileDialog dialog(this, "Seer log file", "", "Logs (*.log);;Text files (*.txt);;All files (*.*)");
+    dialog.setOptions(QFileDialog::DontUseNativeDialog);
     dialog.setAcceptMode(QFileDialog::AcceptSave);
     dialog.setFileMode(QFileDialog::AnyFile);
     dialog.setDefaultSuffix("log");