Fix BlackCore header includes

* Include only what is used
* Use forward declaration when possible
* Sorted includes

refs #598

src/blackcore/contextnetworkproxy.cpp

@@ -9,9 +9,13 @@
 
 #include "blackcore/contextnetworkproxy.h"
 #include "blackmisc/audio/voiceroomlist.h"
-#include <QObject>
-#include <QMetaEnum>
+#include "blackmisc/dbus.h"
+#include "blackmisc/genericdbusinterface.h"
+
 #include <QDBusConnection>
+#include <QLatin1Literal>
+#include <QObject>
+#include <QtGlobal>
 
 using namespace BlackMisc;
 using namespace BlackMisc::Network;