Google Indexing API - Add Ludwig integration

ludwig.json file

{
    "require": {
        "google/apiclient": {
            "version": "^2.0",
            "url": "https://github.com/googleapis/google-api-php-client/archive/v2.17.0.zip"
        }
    }
}

But https://imgur.com/VUBK3IF

1. Warning! The FILES type libraries are not supported by Ludwig automatically.
2. Warning! The CLASSMAP type libraries are not supported by Ludwig automatically.

https://www.drupal.org/docs/contributed-modules/ludwig/ludwig-errors-war... →

Re: #8

@promo-il please read comment #6 here.