3055
3056

Sync all layers and make them build/pass tests again.
Hopefully we won't have to put up with this duplication for long.

Test and trace infrastructure is assumed to be independent of the
layered organization, and so immune to the imperative that each layer be
as simple as possible.
3057

New plan: work up the layers in literate form. Each new layer up should only
add files, not modify any older ones.
3058
3059
3060
3061

Insert code above the 'End Test Initialization' hook, and *below* the
'Test Verification' hook.
3062

Drop some tokenization tests from layer 20 that don't become important
until we add indent-sensitivity.
3063 - trace handles trailing newlines

Unlike other traces, RAISE requires a trailing newline since it might
be printed to screen.
3064 - macros for checking warnings

We sometimes now print extra warnings during teardown, but that's
preferable to hiding a warning the one time we should show it.

(Ideally we'd have levels of warnings.)
3065 - more warnings during tangle