Document how to run openstack-cloud-controller-manager with hack/local-up-cluster.sh

[dims]

There is support for EXTERNAL_CLOUD_PROVIDER=true when you also add CLOUD_PROVIDER and CLOUD_CONFIG for local-up-cluster.sh, we should document how one can easily build a test/dev environment using local-up-cluster.sh

[dims]

please see:

• Use backup location to load cloud config for OpenStack kubernetes/kubernetes#58549
• fix provider-id bad param in local-up-cluster kubernetes/kubernetes#58543

[dims]

oh, the local-up-cluster should be running inside a VM started by OpenStack (to be able to pick up the metadata from either the config drive or the metadata service)

[dims]

see kubernetes/kubernetes#59280

[dims]

with latest k/k master, set the following env vars and then run sudo -E PATH=$PATH ./hack/local-up-cluster.sh (PATH should have etcd binaries)

export EXTERNAL_CLOUD_PROVIDER_BINARY=/home/dims/go/src/git.openstack.org/openstack/openstack-cloud-controller-manager/openstack-cloud-controller-manager
export EXTERNAL_CLOUD_PROVIDER=true
export CLOUD_PROVIDER=openstack
export CLOUD_CONFIG=/etc/kubernetes/cloud-config

[dims]

@hogepodge can you please try this out?