writerfilter: remove unused WW8FFDATA in doctok

Change-Id: I62a5d45a818738fb06b1d80652c0ad6c0aee5f29
writerfilter: remove unused WW8BRC in doctok

Change-Id: I9da4b0d5e003f12474fb11dc4b102e5fad79f11e
writerfilter: remove unused WW8LineProps in doctok

Change-Id: I6fae7739235194c3452634ff8a173f4ab5eac425
writerfilter: drop ww8resource annotation in doctok

This was used as a tag for various classes, but the generated result
wasn't used anywhere, so let's just get rid of it.

Change-Id: I61dc51368177eddb6d04dba94063ba102f4ca1e5