new vault dialog

src/mainwindow.cc

@@ -0,0 +1,21 @@
+#include "mainwindow.h"
+#include <QDebug>
+#include <QFileDialog>
+#include <fstream>
+
+MainWindow::MainWindow(QWidget *parent)
+    : QMainWindow(parent), ui(new Ui::MainWindow) {
+  ui->setupUi(this);
+
+  connect(ui->actionNew, &QAction::triggered, this, [this]() {
+    QString path = QFileDialog::getSaveFileName(this, "Choose vault location",
+                                                QDir::currentPath(),
+                                                "Dull Vaults (*.dull)");
+    if (path.isEmpty()) {
+      return;
+    }
+
+    std::ofstream file(path.toStdString(), std::ios::binary);
+    file.write("TEST", 4);
+  });
+}