fixed bug with empty clientid
fixed bug with empty clientid

erlio/vernemq,erlio/vmq_server,larshesel/vmq_server,erlio/vernemq,erlio/vernemq,mururu/vmq_server,linearregression/vmq_server,erlio/vernemq,erlio/vmq_server,larshesel/vmq_server,dergraf/vmq_server,dergraf/vmq_server,sunnyjain1/vmq_server,dejavu1988/vmq_server