killNode() to nodeKilled()
made nodeKilled signatures match
removed debug variable
updated connect() to qt5 format
removed connect(); put call into Application::nodeKilled

OctreePacketReceiver::nodeKilled() doesn't get called when
NodeList::nodeKilled() is emitted for some unknown reason
removed debug prints
removed debug var
Merge pull request #3012 from wangyix/master

added OctreePacketProcessor::nodeKilled to Application::nodeKilled instead of connecting it to NodeList::nodeKilled