Function write_element_with_fields 

pub fn write_element_with_fields<T: WriteXmlFields>(
    writer: &mut Writer<Cursor<Vec<u8>>>,
    name: &str,
    value: &T,
) -> Result<(), XmlError>

Write a named XML element whose content comes from a WriteXmlFields value.

Writes <name>, calls value.write_xml_fields(), then writes </name>.