Add voters

[sagikazarmark]

I don't really like the Security component in Symfony, because I think it is overcomplicated. One feature I really like though is the Voter next to ACL access checking:

https://symfony.com/doc/master/book/security.html#access-control-lists-acls-securing-individual-database-objects

[saada]

What's the difference between Voters and the currently implemented conditions?