Feature: #EXTBLOG-73 - Add support for disqus.com

See https://jira.typo3.com/browse/EXTBLOG-73

Description

Support for disqus.com was added which allows threaded and interactive comments. To use disqus.com you have to enable it and set your disqus shortname (forum identifier)

plugin.tx_blog.settings.comments {
   disqus = 1
   disqus.shortname = foo-bar
}

The TypoScript above configures / activates the disqus support and replaces the classic comment form and comment listing. The comment counts in the list are also replaced by disqus. Attention: If you have overridden the templates, check the template changes of this patch.