Create marker widget and attempt to add to timeline

app/dialog/about/about.cpp

@@ -30,6 +30,8 @@
 #include "patreon.h"
 #include "scrollinglabel.h"
 
+#include "widget/marker/marker.h"
+
 namespace olive {
 
 AboutDialog::AboutDialog(bool welcome_dialog, QWidget *parent) :
@@ -74,6 +76,9 @@ AboutDialog::AboutDialog(bool welcome_dialog, QWidget *parent) :
   label->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Minimum);
   horiz_layout->addWidget(label);
 
+  Marker* marker = new Marker();
+  horiz_layout->addWidget(marker);
+
   layout->addLayout(horiz_layout);
 
   // Patrons where possible