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* Allow sending ``payer`` and ``description`` when creating preferences.
* Replaced ``MERCADOPAGO_ASYNC`` with the opposite ``MERCADOPAGO_AUTOPROCESS``
setting, since asynchronous processing will never be built in (only the
necessary helpers)
* Fire a signal when a notification is received. The docs mention how to listen
to it, which you might want to do if you'd like to do asynchronous
processing.
* Add a management command to poll unpaid preferences.
* Introduced this changelog.