Merge pull request #53 from tamasd/7.x-1.x

Adds AJAX functionality to the publish/unpublish switch on the walkthrough node page.
Merge pull request #54 from tamasd/7.x-1.x

Simplifies the play dialog.
Merge pull request #55 from tamasd/7.x-1.x

Adds cache clearing to the toggle button.
Change selector for Starting the walkthrough
Merge pull request #56 from Coornail/fix/walkthrough-screening-start-text

Change selector for Starting the walkthrough
Make Groups optional (via module_exists())
Merge pull request #57 from jpstrikesback/if-og

Make Groups optional (via module_exists())
Duplicates the apiv2 endpoint, in order to workaround the new services release.