Merge branch 'vi_grpcTimeoutFix' into 'devbranch'

GRPC : connection timeout issue fix added

Closes MKCLOS/coreosv3/corestudio#331

See merge request !176

grpcclientmdl/grpcclientmdl.go

@@ -49,6 +49,7 @@ func ByteHandler(req *grpcbuildermdl.GRPCRequest, grpcServerURL string) ([]byte,
 			loggermdl.LogError("Failed to create gRPC pool: %v", err)
 			return nil, 0, "", err
 		}
+		defer conn.Close()
 		client := grpcbuildermdl.NewGRPCServiceClient(conn.ClientConn)
 		res, err := client.GRPCHandler(context.Background(), req)
 		if err != nil {