Efficient broadcast overloads for AbstractVectorOfArray

[ChrisRackauckas]

It can broadcast along the linear index. This will make its broadcast performant for most analyses, and so the only indexing performance issue could be from directly using the matrix indexing.

[ChrisRackauckas]

the fallbacks using Cartesians actually do super well. I don't think overloads are needed for speed. It is annoying that it returns a standard Vector{Array} though.

[ChrisRackauckas]

@ScottPJones I know you've been looking at this stuff: do you know how you can add something to say "make it return a VectorOfArray"?

[ScottPJones]

I wish I did, that's the same problem that I've been running into with trying to get the broadcasting of MultiScaleArrays to work, if you don't add specializations for broadcast!, broadcast, it just returns Vector{T}