functional: run container without pid file
functional: run container without pid file

add test to check if a container can run without a pid file

fixes #62

Signed-off-by: Julio Montes <4a43a13347431ef00be7d745d08a5ba1757e840b@intel.com>

bwarden/tests,chavafg/tests,MarioCarrilloA/tests,sboeuf/tests,GabyCT/tests,devimc/tests,clearcontainers/tests,chavafg/tests,devimc/tests,bwarden/tests,MarioCarrilloA/tests,clearcontainers/tests,GabyCT/tests,sboeuf/tests