make deck.js backend compatible with Asciidoctor 1.5.0

NOTE: If you are still using Asciidoctor 0.1.4, use the asciidoctor-v0.1.4 branch
resolves #44 add compatibility with deck.js 1.1.0

- remove explicit permalink if deckjs_version > 1.0.0 (hash extension is part of core)
- set deckjs_version attribute to 1.0.0 if you are still using deck.js 1.0.0