refs #359, fixed loghandler, removed / fine tuning of some output / log messages

see also discussion in #359

src/blackmisc/loghandler.h

@@ -167,6 +167,7 @@ namespace BlackMisc
 
         bool canBeDeleted()
         {
+            if (! m_inheritFallThrough) { return false; }
             static const auto signal = QMetaMethod::fromSignal(&CLogPatternHandler::messageLogged);
             return ! isSignalConnected(signal);
         }