Add KriKri, Devise, and Blacklight

See https://github.com/dpla/heidrun/pull/3, which was closed in order to merge into `develop` instead of `master`.

This adds KriKri and Devise.  It adds Blacklight by way of KriKri.

The Blacklight catalog#index action functions as the application's
home page.

Devise is installed independently of Blacklight.

Per our discussion on Slack, this is OK to merge, so I'll do that.