files(/* options */) {
    if (this._files) {
      return this._files;
    }

    let filesPath = this.filesPath(this.options);
    if (Blueprint._existsSync(filesPath)) {
      this._files = walkSync(filesPath);
    } else {
      this._files = [];
    }

    return this._files;
  }
Used to retrieve files for blueprint.

    @public
    @method files
    @param {Object} options
    @return {Array} Contents of the blueprint's files directory