<http://schema.org/interactionType>
"http://schema.org/CommentAction"^^<http://www.w3.org/2001/XMLSchema#string>
<http://thenextweb.com/apps/2013/09/19/no-more-to-and-fro-boomerang-calendar-plugin-now-lets-you-schedule-meetings-within-a-single-email/>