README examples with `createdAfter` are incorrect

I.e.
```javascript

let response = merge.hris.employees.list({
  createdAfter: "2030-01-01",
})
```

`createdAfter` should be of type `Date` 
OR
the code should be updated to cater for strings being passed

L.E.
Also the `Pagination` examples are missing the `await`