POST /email/create/new

{
    "from": "globalauto@munichre.com",
    "to": "eday@munichre.com",
    "subject": "Automated process complete",
    "body": "Your automation request has successfully
             completed.  Please see attachment for 
             details.",
    "importance": "normal",
    "attachments": [
        {
            "name": "results.xlsx",
            "bytes": "base64string"
        }
    ]
}