set the memory pool for the next hash table too

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
add maximum value for active messages (disabled)

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
normalize external ephemeral memory allocations

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
recompute the reqeuired kmer count

Link: https://github.com/GeneAssembly/biosal/issues/632
Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>