Get rid of a couple of copies of the CC0 text. Add header comment to
CC0 files to remind people editing them what the terms are. Also add
some missing XML headers. The header comments in layouts won't bloat
the binary - they get stripped out before compressing, same as any other
comments.
a general workbench list and an application list for testing. Images in
those lists are either verified good or best available currently. Many
images are still missing.
