fix bug in node_processor, handle_plain
fix bug in node_processor, handle_plain

jxxcarlson/asciidoctor-latex,asciidoctor/asciidoctor-latex,PissedCapslock/asciidoctor-latex,PissedCapslock/asciidoctor-latex,jxxcarlson/asciidoctor-latex,asciidoctor/asciidoctor-latex,jxxcarlson/asciidoctor-latex,asciidoctor/asciidoctor-latex,PissedCapslock/asciidoctor-latex