deleted unnecessary specs for dummy home controller / index
devise user model factory and spec per RailsApps tutorial:
railsapps.github.io/tutorial-rails-devise-rspec-cucumber.html
testing factories for sanity sake per thotbot tutorial:
robots.thoughtbot.com/post/30994874643/testing-your-factories-first
adding Gringotts::User and associated spec tests; needed to tweak spec configuration to make factories load