add template keyword (for GCC)

GUI/Model/Types/SelectionProperty.h

@@ -26,7 +26,7 @@ public:
     void init(const QString& label, const QString& tooltip, const QString& persistentTag)
     {
         m_persistentTag = persistentTag;
-        m_descriptor.init<Catalog>(label, tooltip, &m_p);
+        m_descriptor.template init<Catalog>(label, tooltip, &m_p);
         m_p = Catalog::create(Catalog::types()[0]);
     }