'Creates a working directory for use while building.'

def setup_working_dir(self):

    if self.conf.work_dir:
        self.working_dir = os.path.join(self.conf.work_dir, 'docker')
    else:
        ts = time.time()
        ts = datetime.datetime.fromtimestamp(ts).strftime('%Y-%m-%d_%H-%M-%S_')
        self.temp_dir = tempfile.mkdtemp(prefix=('kolla-' + ts))
        self.working_dir = os.path.join(self.temp_dir, 'docker')
    self.copy_dir(self.images_dir, self.working_dir)
    for dir in self.conf.docker_dir:
        self.copy_dir(dir, self.working_dir)
    self.copy_apt_files()
    LOG.debug('Created    working    dir:    %s', self.working_dir)
