Adds command-line options for this plugin.

def options(self, parser, env=None):
        """
        Adds command-line options for this plugin.
        """
        if env is None:
            env = os.environ
        env_opt_name = 'NOSE_%s' % self.__dest_opt_name.upper()
        parser.add_option("--%s" % self.__opt_name,
                          dest=self.__dest_opt_name,
                          type="string",
                          default=env.get(env_opt_name),
                          help=".ini file providing the environment for the "
                               "test web application.")