Allow Job#queue_signal to take a queue_name

Allow Job state transitions to queue a signal on a particular queue_name
allowing states to be run by specific workers.

app/models/job/state_machine.rb

@@ -51,14 +51,15 @@ def signal(signal, *args)
     end
   end
 
-  def queue_signal(*args, priority: MiqQueue::NORMAL_PRIORITY, role: nil, deliver_on: nil, server_guid: nil)
+  def queue_signal(*args, priority: MiqQueue::NORMAL_PRIORITY, role: nil, deliver_on: nil, server_guid: nil, queue_name: nil)
     MiqQueue.put(
       :class_name  => self.class.name,
       :method_name => "signal",
       :instance_id => id,
       :priority    => priority,
       :role        => role,
       :zone        => zone,
+      :queue_name  => queue_name,
       :task_id     => guid,
       :args        => args,
       :deliver_on  => deliver_on,