Suggestion: add optional query parameters

[bartwttewaall]

Hi there, thank you for writing this plugin! It's been a great help with routing for multilingual websites.
I'd like to suggest an addition: the same approach for optional query parameters.

routes.php

return [
  'english' => [
    'customer/order/<orderId:\d+>?<status:\w+>&<error:\w+>' => [
      'template' => 'customer/order', 'name' => 'customerOrder'
    ]
  ],
  'dutch' => [
    'klant/bestelling/<orderId:\d+>?<status:\w+>&<error:\w+>' => [
      'template' => 'customer/order', 'name' => 'customerOrder'
    ]
  ]
]

template.twig

{{ craft.namedRoutes.getUrl('customerOrder', { orderId: 1234, status: 'paid', error: null }) }}

This would result to:

• English: customer/order/1234?status=paid
• Dutch: klant/bestelling/1234?status=paid