fix the type of block_size

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
don't print number of DNA sequences

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
reserve 4*nodes for actor names

Link: https://github.com/GeneAssembly/biosal/issues/630
Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>