Also fix some unhandled errors.
integration-cli/docker_cli_swarm_test.go:697:19: printf: non-constant format string in call to fmt.Fprintf (govet)
fmt.Fprintf(w, `{"Error":"failed to add veth pair: `+err.Error()+`"}`)
^
integration-cli/docker_cli_swarm_test.go:731:18: printf: non-constant format string in call to fmt.Fprintf (govet)
fmt.Fprintf(w, `{"LocalDefaultAddressSpace":"`+lAS+`", "GlobalDefaultAddressSpace": "`+gAS+`"}`)
^
integration-cli/docker_cli_swarm_test.go:742:19: printf: non-constant format string in call to fmt.Fprintf (govet)
fmt.Fprintf(w, `{"Error":"Unknown address space in pool request: `+poolRequest.AddressSpace+`"}`)
^
integration-cli/docker_cli_swarm_test.go:746:19: printf: non-constant format string in call to fmt.Fprintf (govet)
fmt.Fprintf(w, `{"PoolID":"`+poolID+`", "Pool":"`+pool+`"}`)
^
integration-cli/docker_cli_swarm_test.go:763:19: printf: non-constant format string in call to fmt.Fprintf (govet)
fmt.Fprintf(w, `{"Address":"`+gw+`"}`)
^
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>