A new option, --enable-registry, has been added for starting a local, private registry.
This registry will be shared between all the k3d clusters created with --enable-registry.
The registry container will be removed when the last of them is removed.
Two extra options, --registry-name and --registry-port, have been included for specifying
the hostname and port where the registry will be available.
Signed-off-by: Alvaro Saurin <alvaro.saurin@gmail.com>
