'Pops kwargs from do_install before starting the installation
Args:
kwargs:
\'stop_at\': last installation phase to be executed (or None)'

def _do_install_pop_kwargs(self, kwargs):

    self.last_phase = kwargs.pop('stop_at', None)
    if ((self.last_phase is not None) and (self.last_phase not in self.phases)):
        tty.die("'{0}'    is    not    an    allowed    phase    for    package    {1}".format(self.last_phase, self.name))
