[Feature] Add hasPermissionTo to Roles model

[mgambati]

It will be very useful when dealing with many roles and permissions.

I would write it, but my testing skills is not good enough to make a PR.

[freekmurze]

My thinking is that you it's better to check the permissions of a user, instead of checking the permissions of a role.

The only time you might want to retrieve the permissions is when builiding a screen to administer the permissions of a role. But then you could just loop through the permission relation on role.

[jpmurray]

@freekmurze : just curious, what makes looping through it more of a better option then $role->permissions()->sync($array_for_permissions_id); ?

[freekmurze]

If you want to save using sync is indeed the best option. In the example above I was thinking about rendering a list.