Interrupt also upscale

[R4rum]

The interrupt button currently only interrupts the image generation. However, when working on a big picture, there's that automatic upscaling step to do as well. Personally I'd like the interrupt to truly discard the in-process results (the batch currently in process, not all the batches) and not bother trying to do that upscaling for those incomplete generations.

[Interpause]

I guess this can be done if I implement the interrupt API myself instead of using the official API for it. Need to notify my part of the API that it was interrupted somehow.