Add parallelism and "runtime cleanup" configuration
Add parallelism and "runtime cleanup" configuration

* Test memory-cleanup-at-exit runtime mode (OCAMLRUNPARAM="c=1")
* Run with -j8 because we have plenty of cores on the test machine

gerdstolpmann/ocaml,gerdstolpmann/ocaml,gerdstolpmann/ocaml,gerdstolpmann/ocaml,gerdstolpmann/ocaml