Add a test for mul_generator

        let point2 = EcPoint::from_bytes(&group, &bytes, &mut ctx).unwrap();

        assert!(point.eq(&group, &point2, &mut ctx).unwrap());

    }

    #[test]

    fn mul_generator() {

        let group = EcGroup::from_curve_name(nid::X9_62_PRIME256V1).unwrap();

        let key = EcKey::generate(&group).unwrap();

        let mut ctx = BigNumContext::new().unwrap();

        let mut public_key = EcPoint::new(&group).unwrap();

        public_key.mul_generator(&group, key.private_key().unwrap(), &mut ctx).unwrap();

        assert!(public_key.eq(&group, key.public_key().unwrap(), &mut ctx).unwrap());

    }

}