parallelization params to run-frog

[mihai-sysbio]

While trying to run fbcmodeltests-run-frog via Docker on Human-GEM, it took way too many hours to compute with the default settings, so I tried for a little to manually add workers and failed. It would be great to allow passing of parallelization params to run-frog, since the underlying function FROG.generate_report already has support for it.

[exaexa]

True, we omitted the parameter so far because the script was meant to be a completely simple wrapper... will add asap.