Broad code cleanup.

src/lib-sieve/sieve-common.h

src/lib-sieve/sieve-dump.h

src/lib-sieve/sieve-error-private.h

src/lib-sieve/sieve-error.c

src/lib-sieve/sieve-error.h

src/lib-sieve/sieve-extensions.c

src/lib-sieve/sieve-extensions.h

src/lib-sieve/sieve-generator.c

src/lib-sieve/sieve-generator.h

src/lib-sieve/sieve-interpreter.c

src/lib-sieve/sieve-interpreter.h

src/lib-sieve/sieve-limits.h

src/lib-sieve/sieve-message.c

src/lib-sieve/sieve-message.h

src/lib-sieve/sieve-objects.c

src/lib-sieve/sieve-objects.h