* Makefile.in (nettle_SOURCES): Added sha512.c and sha512-meta.c.

* sha.h: Added SHA-512-related declarations.
* nettle-meta.h: Likewise.

* sha512-meta.c: New file.
* sha512.c: New file.

Rev: nettle/Makefile.in:1.14
Rev: nettle/nettle-meta.h:1.3
Rev: nettle/sha.h:1.2
Rev: nettle/sha512-meta.c:1.1
Rev: nettle/sha512.c:1.1