toy/image_optim — pull request #7 by fbernier (2013-01-16 18:09:46+00:00)
Title: Fix which command on ubuntu

Hi, the 'which' command has no option '-s' on my system (ubuntu 12.10). which makes the command fail and return a bad exit status. I figured just redirecting the output to /dev/null would fix this issue for me while remaining compatible with OSX.