network: fix yaml struct tag
network: fix yaml struct tag

Related to #543.

ybogdanov/go-dockerclient,tarsisazevedo/go-dockerclient,tarsisazevedo/go-dockerclient,ybogdanov/go-dockerclient,paulbellamy/go-dockerclient,csrwng/go-dockerclient,csrwng/go-dockerclient,fsouza/go-dockerclient,davidstack/go-dockerclient,davidstack/go-dockerclient