Track tmp test empty dir.
Fix Github APi rate limit when using Composer package in Travis
Merge pull request #20 from bar/track-test-tmp

Track tmp test empty dir.
Call kill command using an absolute path. Also, update syntax and status codes.

From kill manual page:
Your shell (command line interpreter) may have a built-in kill command.  You may need  to  run  the  command  described  here  as /bin/kill to solve the conflict.