This package is deprecated, as it was dedicated to a similar data-processing
as it was available within CKEditor 4, without ever reaching a state of
being a complete replacement.
Instead, the new data-processing architecture relies on pure DOM
manipulation, providing a much richer API to deal with nodes, elements and
attributes.
This module re-introduces such filter approaches. It is not meant to be a
replacement but an alternative to the previous filtering mechanisms, which
should ease migration from CKEditor 4 based data processing approaches.