Benchmark-unify: map KRB5 format names

Even though these names have only been used in 1.7.9-jumbo-7+unstable
and 1.7.9-jumbo-8-unstable, make sure they are mapped to the names
that will be used for 1.7.9-jumbo-8.
Merge pull request #198 from frank-dittrich/unstable-jumbo

Benchmark-unify: map KRB5 format names