code: function (dest, src, recursive) {
    for (var prop in src) {
      if (recursive && dest[prop] instanceof Object && src[prop] instanceof Object) {
        dest[prop] = defaults(dest[prop], src[prop], true);
      } else if (! (prop in dest)) {
        dest[prop] = src[prop];
      }
    }
  
    return dest;
  }
docs: Merge default values.
  
  @param {Object} dest
  @param {Object} defaults
  @return {Object}
  @api public