make shutdown? method, which plugins can override

Author: nevans

lib/resque/worker.rb

@@ -108,7 +108,7 @@ def work(interval = 5, &block)
       startup
 
       loop do
-        break if @shutdown
+        break if shutdown?
 
         if not @paused and job = reserve
           log "got: #{job.inspect}"
@@ -265,6 +265,11 @@ def shutdown!
       kill_child
     end
 
+    # Should this worker shutdown as soon as current job is finished?
+    def shutdown?
+      @shutdown
+    end
+
     # Kills the forked child immediately, without remorse. The job it
     # is processing will not be completed.
     def kill_child