add support for multiple authors
add support for multiple authors

azuwis/asciidoctor-fopdf,getreu/asciidoctor-fopub,asciidoctor/asciidoctor-fopub,getreu/asciidoctor-fopub,getreu/asciidoctor-fopub,asciidoctor/asciidoctor-fopub,asciidoctor/asciidoctor-fopub,azuwis/asciidoctor-fopdf