Add About Dialog and PCL LICENSE

mainwindow.cpp

@@ -17,6 +17,7 @@
 #include <QThreadPool>
 #include "loadrunable.h"
 #include "markedfiles.h"
+#include "about.h"
 
 #ifdef __linux__
 #include <sys/ioctl.h>
@@ -152,6 +153,10 @@ MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent)
     dockMenu->addAction(databaseViewDock->toggleViewAction());
     menuBar()->addMenu(dockMenu);
 
+    QMenu *helpMenu = menuBar()->addMenu(tr("Help"));
+    helpMenu->addAction(tr("About Tenmon"), [this]{ About about(this); about.exec(); });
+    helpMenu->addAction(tr("About Qt"), [this](){ QMessageBox::aboutQt(this); });
+
     setupSigterm();
     QSettings settings;
     restoreGeometry(settings.value("mainwindow/geometry").toByteArray());