thorium: reduce multiplexer timeout

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
performance: add a script to measure single rank performance

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
performance: add messaging rate in toolkit

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>