Provide Programmatic way to set undercloud

[smalleni]

Instead of assuming the first host is always the undercloud, there should be a programmatic way through QUADS cli to set the undercloud host in a cloud. This is needed for the automated OpenStack work, since the code will decide the host best suited for the undercloud and it should be able to set the undercloud through QUADS cli.

[smalleni]

@kambiz-aghaiepour

[sadsfae]

This is a dependency for #13