Automatic broadcasting

[jank324]

In #116, we added a vectorised way of using Cheetah. This means that instead of either one of these

elem1 = Drift(length=0.3142)
elem2 = Drift(length=torch.tensor(0.3142))

you have to remember to set properties in the correct dimension even if you are not using multiple dimensions or only a single value for that property

elemt3 = Drift(length=torch.tensor([0.3142])

By introducing automatic broadcasting (in a similar way to how PyTorch does it), we want to be able to use either one of the examples in the first code block while tracking, for example, a beam with 1000 different properties.

[cr-xu]

Is this now considered solved by #208?

[jank324]

Is this now considered solved by #208?

Yes!