baseclient.py: - select was not used properly, creating a busy loop - added stop function in TCPConnection mainwindow.py: - fixed behaviour when a connection is broken: a message is shown, and the node is removed from the tree Change-Id: I7223dfd9ea027681aff089f2fa16e134a16a7b84 Reviewed-on: https://forge.frm2.tum.de/review/20922 Tested-by: JenkinsCodeReview <bjoern_pedersen@frm2.tum.de> Reviewed-by: Enrico Faulhaber <enrico.faulhaber@frm2.tum.de>