Get permission and role class from method instead of the configuration in traits

[illambo]

Edit: I push PR #2623 for a more complete solution.

This PR add the (little) ability to override role and permission model class in traits, this can "facilitate" (in a non-exhaustive manner, see discuss #2571) some cases of applications with package used on multiple databases (without the need to modify the configuration at runtime).

[parallels999]

Must be the same change for Models?? https://github.com/spatie/laravel-permission/blob/0e593bb9e6808cc55c67f150878b0847f20b9036/src/Models/Permission.php#L61 https://github.com/spatie/laravel-permission/blob/0e593bb9e6808cc55c67f150878b0847f20b9036/src/Models/Role.php#L70

[illambo]

Good point, later I check this. Thanks

[drbyte]

still reviewing this and the other PR