build: reanimate the dead

Fix build with ndn-cxx 0.7.1 and ChronoSync 0.5.3

* Adapt to new API
* Upgrade to Qt5
* Several other bugs

Refs: #4563, #4087
Change-Id: Ic55d687caade08f557f9b9ec3e9569bc96798710
diff --git a/src/discovery-panel.hpp b/src/discovery-panel.hpp
index 1b5bd92..473283f 100644
--- a/src/discovery-panel.hpp
+++ b/src/discovery-panel.hpp
@@ -13,6 +13,7 @@
 
 #include <QDialog>
 #include <QStringListModel>
+#include <QItemSelection>
 
 #ifndef Q_MOC_RUN
 #include "chatroom-info.hpp"