Don't echo on no-op runs

Every time a cron job writes to stdout on success, a UNIX admin trims his beard. Won't someone think of the beards?!

Seriously, this script runs from cron every 5 minutes, and we get every one of those echos as an email to root@. No more!
Merge pull request #257 from jldugger/master

Don't echo on no-op runs