Batch Explorer Should Turn off Autoscale before delete or prevent

[bgklein]

Customer informed that there is no mention of needing to alter the scaling formula in this message. Since Batch Explorer is indicated in the Azure Portal as an endorsed tool to use to manage Azure Batch pools, customer expected a more descriptive error message would be displayed if they need to do something as simple as changing my scaling formula. That did fix the issue. The error message they get from Batch Explorer when customer try to delete the node is as the image attached.