It will help feature 10239, in order to automate the deployment of the
VCA without needing to deploy OSM.

When the option is enabled in the installation, in the end a string will
be printed out with the command to be executed in OSM to register the
installed VCA.

Change-Id: I1b284a5a650b50e89c07a6d08507406823c6cc2d
Signed-off-by: David Garcia <david.garcia@canonical.com>