- fix problem where desktop sharing client doesn't stop when server stops

...button-client/html-template/bbb-deskshare-applet-0.64.jar

...a/org/bigbluebutton/deskshare/client/DeskshareClient.java

...ava/org/bigbluebutton/deskshare/client/DeskshareMain.java

...utton/deskshare/client/net/NetworkConnectionListener.java

...gbluebutton/deskshare/client/net/NetworkStreamSender.java