don't use timer unless it's the main actor

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
remove some trailing spaces

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
add a timer for input streaming to kmer stores

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