FU: Revert integration with XMLWriter & import options; copyright stuff

Realized that, since html_() now returns a string, it's just as easy to
just pass that to fu->set_body(); no need for integration complexity.

Combined import options don't save much typing, not worth the overhead
either.

FU/XMLWriter.pm

@@ -289,3 +289,11 @@ L<DSL::HTML>, but its syntax isn't quite as nice.
 And there's also L<HTML::FromArrayref>, L<HTML::Tiny>, L<HTML::Untidy> and many
 more modules on CPAN. In fact I don't know why you should use this module
 instead of whatever is available on CPAN.
+
+=head1 COPYRIGHT
+
+MIT.
+
+=head1 AUTHOR
+
+Yorhel <projects@yorhel.nl>