Added an option to fail jobs if any output is detected.  This was primarily intended for the cases where a PHP warning is printed, but no exception is thrown (like for undefined variables).  By default, jobs still succeed those cases.  After setting 'fail_on_output' to true, jobs with any output will fail with the output included in the 'error' database column.
Made spacing adjustments per Jose's request.
Merge pull request #34 from mmcev106/master

Added an option to fail jobs if any output is detected.  This was primar...