There are a few document properties (author, description, keywords) that
should automatically be made meta tags if they exist on export. These were
currently being checked as part of an and block that would evaluate both,
creating the string, then just return a newline on success, meaning the
meta tags were never added to the document (since they're part of a larger
concat that never got the string added to it). This patch wraps the needed
logic check into a when, then concats the tag creation and newline addition
to return.