Merge pull request #558 from frank-dittrich/bleeding-jumbo

First revision of testing for different tunable costs among hashes
Reduce chatter
Let 9 more formats report tunable cost values

sha256crypt
sha256crypt-cuda
sha256crypt-opencl
sha512crypt
sha512crypt-cuda
sha512crypt-opencl
PBKDF2-HMAC-SHA256
PBKDF2-HMAC-SHA256-opencl
SunMD5