Add MD2 message digest implementation
* cipher/md2.c: New. * cipher/md.c (digest_list): add _gcry_digest_spec_md2. * tests/basic.c (check_digests): add MD2 test vectors. * configure.ac (default_digests): disable md2 by default.
Some minor indentation fixes by wk.
- Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>