Unregisters given layout.

        :param name: Layout name.
        :type name: unicode
        :param layout: Layout object.
        :type layout: Layout
        :return: Method success.
        :rtype: bool

def unregister_layout(self, name):
        """
        Unregisters given layout.

        :param name: Layout name.
        :type name: unicode
        :param layout: Layout object.
        :type layout: Layout
        :return: Method success.
        :rtype: bool
        """

        if not name in self:
            raise umbra.exceptions.LayoutRegistrationError("{0} | '{1}' layout is not registered!".format(
                self.__class__.__name__, name))

        del (self.__layouts[name])
        return True