At some point,
nine-track fixtures become unwieldy to copy/paste by hand. Sometimes you add new HTTP request to a
show page and wind up needing to add a new fixture to 20 tests. That is not fun.
Instead of this, we are trying out to use
concat with a set of defaults:
// In our fake-server.js fakeServer.userShowDefaults = [ 'first-fixture', 'proxy' ];