Use gemspec to define dependency
resque 1.25.1 seems requiring yaml
Fix test failure
Display arguments in old style. I don't see any benefit in the
following commit to resque.
https://github.com/resque/resque/commit/dcb9bce2f9e1d70cb846732a67078f7eacf0e46d#diff-f384147196b88f2c83e38e710f7bf041