Improve valid() for clipperz, fixes issue #457
Merge pull request #470 from frank-dittrich/bleeding-jumbo

Improve valid() for clipperz, fixes issue #457
Improve valid() for openssl-enc, fixing #498

A segfault was caused by am empty "known plaintext" field at the
end of the hash.
Improve valid() for django format, fixing issue #460
Merge pull request #471 from frank-dittrich/bleeding-jumbo

Improve valid() for openssl-enc, fixing #498