allow the features to succeed on MacOS (tested on Lion)
Respect new signal behavior as described in http://hone.heroku.com/resque/2012/08/21/resque-signals.html when `TERM_CHILD` environment variable is set. In this case, ignore the command-line options for SIGTERM and a `TERM` signal will pass along a `TERM` signal to all the parents.
Applies to resque-1.22 and above, and will be the default signal behavior in resque-2.0.
Merge pull request #74 from jjulian/topic-term_child

Respect TERM_CHILD env var