Moving solver between devices (multiple GPUs)

Hi, thank you for the great package.

I'm wondering if it's possible to move a `CholeskySolverF` between different devices. Currently the solver is placed on the device corresponding to its input data. 

In my context I have many cholesky solver objects in a large dataset, and I need to readily move them to different gpus inside a torch training loop. Is this possible?

Thanks.