Add Daffodil IO for Apache Beam

From https://daffodil.apache.org/:

> Daffodil is an open source implementation of the DFDL specification that uses these DFDL schemas to parse fixed format data into an infoset, which is most commonly represented as either XML or JSON. This allows the use of well-established XML or JSON technologies and libraries to consume, inspect, and manipulate fixed format data in existing solutions. Daffodil is also capable of the reverse by serializing or “unparsing” an XML or JSON infoset back to the original data format.
>
We should create a Beam IO that accepts a DFDL schema as an argument and can then produce and consume data in the specified format. I think it would be most natural for Beam users if this IO could produce Beam Rows, but an initial version that just operates with Infosets could be useful as well.

Imported from Jira [BEAM-9189](https://issues.apache.org/jira/browse/BEAM-9189). Original Jira may contain additional context.
Reported by: bhulette.