hub: wrap some proxy server calls in try/except, since they are causing tracebacks that disconnect clients (bad).
hub: wrap some proxy server calls in try/except, since they are causing tracebacks that disconnect clients (bad).

tscholl2/smc,sagemathinc/smc,tscholl2/smc,sagemathinc/smc,tscholl2/smc,tscholl2/smc,DrXyzzy/smc,DrXyzzy/smc,tscholl2/smc,DrXyzzy/smc,sagemathinc/smc,sagemathinc/smc,DrXyzzy/smc