So I pushed a more complete layering/base64 implementation.
There's 10 commits now, so eventually they'll get squashed. But It's ready for a real PR review now, not just a preliminary look see. It implements base64_MIME, gzip, lineFolded_IMF, and lineFolded_iCalendar layer transforms. Not yet done: quoted printable, encodedWord, other compressors, AIS,.... However, I believe these can be added quite straightforwardly now. https://github.com/apache/incubator-daffodil/pull/61
