Changed all status to start with Uppercase letters, made 3 properties required.
Changed all the status to start with Uppercase letters because they are
publicly visible. Also changed required=True to False for created_by,
modified_by property to allow site admin to create and modify tasks. Also
changed required=True to False for history to allow history not to be written
until the task is published.
from django.dispatch import Signal
class_prepared = Signal(providing_args=["class"])
pre_init = Signal(providing_args=["instance", "args", "kwargs"])
post_init = Signal(providing_args=["instance"])
pre_save = Signal(providing_args=["instance", "raw"])
post_save = Signal(providing_args=["instance", "raw", "created"])
pre_delete = Signal(providing_args=["instance"])
post_delete = Signal(providing_args=["instance"])
post_syncdb = Signal(providing_args=["class", "app", "created_models", "verbosity", "interactive"])