Add support for host:port:port

This adds support for supplying for example:
"127.0.0.1:80:80/tcp" to docker-compose.yaml and converting it to it's
corresponding Kubernetes / OpenShift hostIP.

This commit also refactors the loadPorts function of compose.go

Closes https://github.com/kubernetes-incubator/kompose/issues/335

pkg/kobject/kobject.go

@@ -91,5 +91,6 @@ type EnvVar struct {
 type Ports struct {
 	HostPort      int32
 	ContainerPort int32
+	HostIP        string
 	Protocol      api.Protocol
 }