Turn the HTTP style headers into AWS Object params
function toAwsParams(file) {
  var params = {};

  var headers = file.s3.headers || {};

  for (var header in headers) {
    if (header === 'x-amz-acl') {
      params.ACL = headers[header];
    } else if (header === 'Content-MD5') {
      params.ContentMD5 = headers[header];
    } else {
      params[pascalCase(header)] = headers[header];
    }
  }

  params.Key = file.s3.path;
  params.Body = file.contents;

  return params;
}