Method pack8

src/pack_ints.rs:310–312

Doesn't use impl_u8!() because it would copy unnecessary.

(v: &mut [Self], out: &mut Vec<u8>)

    impl_unreachable!(u16, pack16, unpack16);
    // Doesn't use impl_u8!() because it would copy unnecessary.
    fn pack8(v: &mut [Self], out: &mut Vec<u8>) {
        pack_bytes(v, out);
    }
    fn unpack8<'a>(
        input: &mut &'a [u8],
        length: usize,