Keep array elements that are NOT in a list of indexes

[aplavin]

@mbauman

You can also use InvertedIndices.jl. I think it should be one of the more efficient methods these days.

InvertedIndices is better than it was before, but still tends to be several times slower than deleteat!(copy(A), I) (just Base, no dependencies) or @delete A[I] (Accessors).