Salt option could be deprecated

[d47081]

Hi and thanks for your work!

I found this crate requires the salt argument in hash_encoded example,
but it usually marked as deprecated everywhere, at least in same PHP method:

https://www.php.net/manual/en/function.password-hash.php

Warning

The salt option is deprecated. It is now preferred to simply use the salt that is generated by default. As of PHP 8.0.0, an explicitly given salt is ignored.

What do you think about?

[mrijkeboer]

Hi @d47081,

Thanks for opening this issue. This library is based on the original (reference) Argon2 implementation. This original implementation also requires the salt argument in hash_encoded. Since this behavior is present in the reference implementation I'm not in favor of changing this.