Update the base encoder

[Th3Mouk]

Hello @djoos,

I would make a PR but before, I'd like to have your opinion.

What are you thinking to update the source code and documentation from sha1 encoder to sha512 ? With a default iteration to 5000.

This configuration is the default one of Symfony, see here. This allow to get a basic configuration enough for non critical applications.

[djoos]

Hi @Th3Mouk,

thanks for reaching out: yes, that definitely makes sense!

Kind regards, David