Milestone 8 UX: folder tree workflows, about dialog, and app icon polish

src/profiles_tree_widget.cpp

@@ -0,0 +1,11 @@
+#include "profiles_tree_widget.h"
+
+#include <QDropEvent>
+
+ProfilesTreeWidget::ProfilesTreeWidget(QWidget* parent) : QTreeWidget(parent) {}
+
+void ProfilesTreeWidget::dropEvent(QDropEvent* event)
+{
+    QTreeWidget::dropEvent(event);
+    emit itemsDropped();
+}