Now a user can select a provider using global flag
--provider=openshift to select openshift provider
or --provider-kubernetes to select kubernetes provider
if nothing is provided kubernetes is the default provider.
Fixes#179
We had Command and Args together with Entrypoint in Kompose object.
This doesn't make much sense, as Entrypoint and Command are same thing.
I've removed Entrypoint from Kompose object in favor of Command to keep
same naming convensions as in Kubernetes.
Entrypoint from docker-compose.yml is now saved to Command and Command
is saved to Args (http://kubernetes.io/docs/user-guide/containers/).
docker-compose.yml | Kompose object
-------------------|---------------
Entrypoint | Command
Command | Args
