c3_fmt.c: support ./john --list=format-tests --format=crypt --subformat=md5crypt

(at least for all subformats supported on the current system)
c3_fmt.c: Print errors to stderr instead of stdout
luks2john.c, use %zu for sizeof(), to fix compiler warning on linux-x86
Merge pull request #535 from frank-dittrich/bleeding-jumbo

Some small bleeding jumbo fixes