Fix queued_email test
Fix queued_email test

  Refer to fixture id's by label, not hard-coded "magic number".
  Completes revision of mailer tests

raysuelzer/mushroom-observer,JoeCohen/mushroom-observer,MushroomObserver/mushroom-observer,JoeCohen/mushroom-observer,pellaea/mushroom-observer,raysuelzer/mushroom-observer,pellaea/mushroom-observer,JoeCohen/mushroom-observer,raysuelzer/mushroom-observer,MushroomObserver/mushroom-observer,pellaea/mushroom-observer,JoeCohen/mushroom-observer,MushroomObserver/mushroom-observer,MushroomObserver/mushroom-observer,pellaea/mushroom-observer,raysuelzer/mushroom-observer,JoeCohen/mushroom-observer,raysuelzer/mushroom-observer,JoeCohen/mushroom-observer,raysuelzer/mushroom-observer,pellaea/mushroom-observer,raysuelzer/mushroom-observer,pellaea/mushroom-observer,MushroomObserver/mushroom-observer,JoeCohen/mushroom-observer,pellaea/mushroom-observer,MushroomObserver/mushroom-observer,MushroomObserver/mushroom-observer