[feature/crypto] Add get_name() method to drivers

This will allow us to actually properly differentiate between the available
drivers.

PHPBB3-11610
[feature/crypto] Add acp settings for selecting password hashing algorithm

This change will add a basic drop-down list for selecting the used password
hashing algorithm.

PHPBB3-11610
[feature/crypto] Reduce complexity of migrations file

PHPBB3-11610