FormatRange will format a valid http Range header.

ContentLength entity-header field indicates the size of the entity-body, in decimal number of OCTETs, sent to the recipient or, in the case of the HEAD method, the size of the entity-body that would have been sent had the request been a GET.

ContentType entity-header field indicates the media type of the entity-body sent to the recipient or, in the case of the HEAD method, the media type that would have been sent had the request been a GET.

ETag response-header field provides the current value of the entity tag for the requested variant.

LastModified entity-header field indicates the date and time at which the origin server believes the variant was last modified.

Location response-header field is used to redirect the recipient to a location other than the Request-URI for completion of the request or identification of a new resource.