added slider for Number of images batch (analog to batch count in webui)

[Nitomash]

Hi. I started your plugin on my own machine. And I had some troubles with using batch size (Number of images) due to my weak videocard. So i added batch count (Number of images batch) with range up to 100 to have power of generating many pics on my small videocard. I think that this update could be useful for some other users Thanks for your work