Update to released version of ember-prism (#702)
Update to released version of ember-prism (#702)

This is a followup to #671, thanks to this release:
https://github.com/brandonjmckay/ember-prism/pull/18#issuecomment-250299107
travis-ci/travis-web,travis-ci/travis-web,fotinakis/travis-web,fotinakis/travis-web,fotinakis/travis-web,travis-ci/travis-web,fotinakis/travis-web,travis-ci/travis-web