Added tests for AsyncResult.traceback KeyError (afd28) when using KeyValueStoreBackend
Added tests for AsyncResult.traceback KeyError (afd28) when using
KeyValueStoreBackend

frac/celery,ask/celery,frac/celery,WoLpH/celery,WoLpH/celery,cbrepo/celery,cbrepo/celery,ask/celery