post https://{app}.{filespin}.{io}/api/v1/user/settings/watermark
There are two steps to update watermark with the optional first step.
STEP 1: to upload a new watermark (optional)
STEP 2: to update the watermark placement and scaling and optionally confirm the file uploaded in STEP 1 as the new watermark.
STEP 1(optional): Upload watermark file
Upload a image as watermark using multipart/form-data HTTP POST
Note that the uploaded file is not set as Watermark immediately and must be confirmed via another API call.
###### Watermark image must be JPG or PNG and must not exceed [1012px Width, 768px Height, 500 KB File Size]