add Faker provider

[IonBazan]

This PR adds simple Faker integration. Since nelmio/alice allows to use <(My\Awesome\Suit::HEART)> notation, there is no point for enum() generator but I think randomEnum() is still valid.

Registering the provider in v1 required some manual work in services.yaml. Do you think we could automate that with bundle configuration like this:

elao_enum:
  nelmio_alice:
    aliases:
       Suit: App\Enums\Suit
       Permissions: App\Enums\Permissions

Would that make sense?

[ogizanagi]

I think there is not much benefit to have a bundle config for this, since registering the provider in Alice is done this way:

services:
  Elao\Enum\Bridge\Faker\Provider\EnumProvider:
    arguments:
      - Suit: App\Enums\Suit
        Permissions: App\Enums\Permissions
  tags: ['nelmio_alice.faker.provider']

which is simple enough not to bother about introducing another conditional config entry.

[ogizanagi]

Thanks @IonBazan.