Split multi-part STL

Sometimes one gets an STL file that has multiple parts in it, and one would like to extract the parts separately (e.g., recently, I wanted to extract a single link from someone's chainmail STL). One could use Meshmixer or something like that, but a simpler solution would be nicer.

I made a [simple javascript page](https://htmlpreview.github.io/?https://raw.githubusercontent.com/arpruss/stlutils/master/split.html) that does that. You just select a file, and then you can download the parts sep