Remove turbolinks
Add Devise for authentication

- Add Devise dependency and associated app files
- Change KriKri gem's branch.  ('add-login' is the topic branch
  that contains new login functionality.)
- Add installation note to README.md

I don't think that config/initializers/devise.rb really wants to be
checked in to version control.  I plan to change this when I learn
the correct way around this.
Revert "Add Devise for authentication"

This reverts commit 19d93373f599ed5962f5547848a5e3f9d80d222f.
Add KriKri, Devise, and Blacklight

See the comments for 19d93373, which had to be reverted.  It has
been re-applied, with Blacklight added.

The Blacklight catalog#index action functions as the application's
home page, and the Blacklight installation had to be changed not
to install Devise.
Remove turbolinks from Gemfile