Added 'doctype' configuration entry
Merge pull request #18 from chkal/doctype

Added 'doctype' configuration entry
Aligned the README.adoc config options with the impl
Merge pull request #19 from bleathem/readme-fix

Aligned the README.adoc config options with the impl
add support for passing attributes to Asciidoctor
Merge pull request #20 from mojavelinux/attributes

add support for passing attributes to Asciidoctor
Add instructions for using attributes option