Combining Lux.jl with IPNewton() for Optimization

[ChrisRackauckas]

@paul188

Specifically, to convert an array of weights and biases in the Optimization routine to a ComponentVector is difficult.

It’s one line, convert(CType,p) where CType is the typeof(ComponentArray(nn_p)) which can just be computed at the Lux.setup outside of the loss function so CType can just be a constant. It’s literally one line, delete all of this.