core: configure memory system on Blue Gene/Q

Heap usage:

Before:
Distribute vertices 13845397504 / 17163091968
Distribute arcs 15820914688 / 17163091968

After:
Distribute vertices 11727929344 / 17163091968
Distribute arcs 13173444608 / 17163091968

Link: https://github.com/GeneAssembly/biosal/issues/828
Link: https://gist.githubusercontent.com/sebhtml/5ba50e2a292ff80d4fb5/raw
Cc: Hal Finkel <hfinkel@anl.gov>
Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>