Window validate fails for a few reasons

[zacsketches]

getting index out of range errors as I prune the slice.

Then getting dups when I append values that are "in" where I is beyond the array.

I think the right thing here is to make the Window data structure a map[hash]*Record delete is provide by the map as well as dealing with duplicates. Since I don't care about the order of the Records in the window this will probably work.

[zacsketches]

Closed by commit 3b9a81e