OnTime API: Downloading Order Signatures

The following endpoint should be used when downloading a signature from an order:
REST API:    GET  /api/order/signature
The types of signatures that can be downloaded are as follows:
1 = Collection
2 = Delivery
The type of signature desired and relative order ID or tracking number should be used as parameters within the URL of the request:
/api/order/signature?orderID=f80fe008-ad86-4b23-9210-4996020f35b1&signatureType=2
If successful, the contents of the signature will be contained within the response body as a Base64 encoded Byte array string. If no signature of the given type exists for that order, the response will appear as null.