support config file on s3
support config file on s3

xindaya/parameter_server,avantcredit/parameter_server,ashhher3/parameter_server,avantcredit/parameter_server,avantcredit/parameter_server,xindaya/parameter_server,dmlc/parameter_server,ashhher3/parameter_server,ashhher3/parameter_server,dmlc/parameter_server,avantcredit/parameter_server,dmlc/parameter_server,xindaya/parameter_server,xindaya/parameter_server,dmlc/parameter_server,ashhher3/parameter_server