message: Clean up code example in docs
diff: * function outMap (action, meta) {
  * const filtered = { }
  * for (const i in meta) {
  - * if (['id', 'time'].indexOf(i) !== -1) {
  + * if (ALLOWED_META.includes(i)) {
  * filtered[i] = meta[i]
  * }
  * }
  