Prompt for Singin from API test
Prompt for Singin from API test

If you're not logged into Keystone, previously the API testing harness
would should a gibberish error. Now it redirects the user and prompts
them to sign in!

w01fgang/keystone-test-project,keystonejs/keystone-test-project,w01fgang/keystone-test-project,keystonejs/keystone-test-project