fix race condition in make mock

Link: https://github.com/GeneAssembly/biosal/issues/72
Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
fix link in API documentation

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
remove threads from node constructor

Link: https://github.com/GeneAssembly/biosal/issues/79
Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
add -threads-per-node all to use all cores

Link: https://github.com/GeneAssembly/biosal/issues/81
Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
support asymmetric number of threads

With: mpiexec -n 32 ./a.out -threads-per-node 32,244,4

Link: https://github.com/GeneAssembly/biosal/issues/82
Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>