code: function processRFC822Node(node, options) {
      options = options || {};
      var message = mimeParser(node.body || ''),
          data = [].concat(getBasicFields(node, options));
  
      data.push(envelope(message.parsedHeader));
      data.push(createBodystructure(message, options));
      data = data.concat(
              node.lineCount
          ).
          concat(getExtensionFields(node, options));
  
      node.text = message.text;
  
      data.node = node;
      return data;
  }
docs: Processes a node with content-type=message/rfc822
  
  @param {Object} node A tree node of the parsed mime tree
  @param {Object} [options] Optional options object (see createBodystructure for details)
  @return {Array} BODYSTRUCTURE for a text part