This is a Lokka plugin to add "+1 Button" link.
Run these commands:
$ cd public/plugin
$ git clone git://github.com/nkmrshn/lokka-plusone.git
You can set options in the admin page [Plugins]->[Pluseone].
There are two helper methods.
One is "plusone_js" to output JavaScript for +1 button.
<script type="text/javascript" src="https://apis.google.com/js/plusone.js"></script>
Antoher is "plusone" and it will output g:plusone(DOM) or div(HTML5) tag.
<g:plusone size="medium" count="false" lang="ja"></g:plusone>
<div class="g-plusone" data-size="medium" data-count="false" data-lang="ja"></div>