Fix Double-Sending Command

The command for clearing the histogram was sent twice, one time ignoring
if the action originated on the server creating an endlees loop...

src/clientgui.cpp

@@ -256,7 +256,6 @@ void ClientGui::fillEventsIntoHistogram(const QString& adcchannels)
 
 void Fp311Online::ClientGui::clearHistogram(const bool fromServer)
 {
-    sendSimpleActiontoServer(Protocol::Action::clearHistogram);
     for (int i = 0; i < ExperimentState::NumberOfAdcChannels - 1; i++)
         _histo->SetBinContent(i, 0);
     _histo->ResetStats();