Allow CelerySignalProcessor to handle signals inside a transaction

[Enorio]

Is it possible to split the code inside CelerySignalProcessor to handle invocations of the shared_task() inside a transaction, to avoid getting this problem detailed in the celery documentation?

In order to add the delay_on_commit, I need to override handle_save, handle_pre_delete, handle_delete, prepare_registry_delete_related_task and prepare_registry_delete_task just to change one line.