lsh and nettle: .c-files include config.h first, then system
files, and finally spki files. .h-files never include config.h,
and they include system files before spki files.

Rev: src/spki/ChangeLog:1.63
Rev: src/spki/certificate.c:1.28
Rev: src/spki/configure.ac:1.8
Rev: src/spki/names.c:1.3
Rev: src/spki/parse.c:1.19
Rev: src/spki/parse.h:1.18
Rev: src/spki/reduce.c:1.5
Rev: src/spki/tag.c:1.14
Rev: src/spki/tools/misc.c:1.3
Rev: src/spki/tools/spki-check-signature.c:1.5
Rev: src/spki/tools/spki-make-signature.c:1.5
Rev: src/spki/verify.c:1.4