first(type) {
    let collection = this.collectionForType(type);
    let record = collection[0];

    return this._hydrate(record, dasherize(type));
  }
Returns the first model in the database.

    ```js
    let post = blogPosts.first();
    ```

    N.B. This will return `null` if the schema doesn't contain any records.

    @method first
    @param type
    @public