Improve error messages

PHP minimum version is now 7.4.

---

Error messages can now use :nif placeholder that will be replaced by the failing nif value.
The package comes with

<?php

return [
    "invalidNIF" => "':attribute' não é um NIF válido.",
    ...
];

but if you publish and replace with (ex.)

<?php

return [
    "invalidNIF" => "':attribute' com valor ':nif' não é um NIF válido.",
    ...
];

Will get the value in the message as well.

Adds CompanyNIF validator

Adds CompanyNIF Rule.

Updated error messages

Fix error messages

Validation rules relevant to Portugal

Version 1.0

Added

• Everything