lib/plugins/config/config.js/Config/constructor
class Config:  constructor(serverless, options) {
    this.serverless = serverless;
    this.options = options;

    this.commands = {
      config: {
        usage: 'Configure Serverless',
        configDependent: false,
        commands: {
          credentials: {
            usage: 'Configures a new provider profile for the Serverless Framework',
            lifecycleEvents: [
              'config',
            ],
            options: {
              provider: {
                usage: `Name of the provider. Supported providers: ${humanReadableProvidersList}`,
                required: true,
                shortcut: 'p',
              },
            },
          },
        },
      },
    };

    this.hooks = {
      'before:config:credentials:config': () => BbPromise.bind(this).then(this.validate),
      'after:config:credentials:config': () => BbPromise.bind(this).then(this.track),
    };
  }