Swith to shields.io and add npm version
Update README
Merge pull request #52 from Mogztter/issue-50

Add npm badges to README
Merge pull request #54 from Mogztter/readme

Update README
Update to Asciidoctor 1.5.1.

* Add namespace to lang attribute in the DocBook 5 backend test,
  to conform with the bugfix upstream.
Release version 1.5.1.
Merge pull request #59 from nawroth/master

Asciidoctor 1.5.1 upgrade.