This also adds some code for canaries, and unifies crypto_{kem,sign}

The previous formatting did not immediately stabilize,
and the resulting formatting is somewhat arbitrary.
Manually inserting linebreaks seems to make more sense.

Separating this into principal and auxiliary submitters was
chosen by NIST. If we do not do the same thing, we would have to
decide how to order names. People seem to have opinions on ordering.