This class declares the controllers we want to use and consequently,
which views in which orders we present to the user.
Reuse the Welcome controller from subiquity by reimporting it in
system_setup.client.controllers.
Redefine the restart functionality to not depends on snap.
This controller and view inherits from the subiquity identity, but
remove the "hostname" field. We are using composition over inheritance
for identityController as the UI builder is basing on the order of
declared elements as class variable and we can’t override that in the
metaclass when inheriting.
Jean-Baptiste Lallement