upload
fun upload(file: File, email: Email, accessToken: String, gravatarUploadListener: GravatarListener<Unit, ErrorType>)
Uploads a Gravatar image for the given email address.
Parameters
file
The image file to upload
email
The email address to associate the image with
accessToken
The bearer token for the user's WordPress/Gravatar account
gravatarUploadListener
The listener to notify of the upload result