message: readme with updated disconnect example
diff: @@ -156,6 +156,9 @@ console.log(tenants || xero.tenants)
  }
  }
  ]
  +
  +// You can also remove a connection by passing `disconnect()` the `.id` which is that tenant's connection id.
  +await xero.disconnect(xero.tenants[0].id)
  ```
  ---
  