[5.7] Always show seeder info

[laurencei]

There is currently no default seeder output.

For example - if your DatabaseSeeder looks like this:

class DatabaseSeeder extends Seeder
{
    public function run()
    {
         factory(\App\User::class)->create();
    }
}

and you run db:seed - you get:

That is because the Seeding: xxx is only added if you use ->call(Seeder::class) inside your seeds.

This PR adds a default

and if you are running multiple seeders

Closes #11375 from 2015 :)