Element matches and closest

[toastal]

So these two require polyfills which doesn't fit the normal mold of what's in Element.js, but I think these are going to be useful functions for a lot of people... including myself for SlamData.

I made an example a while back: https://codepen.io/toastal/pen/dozqRj?editors=0010

[garyb]

Neither of these are part of a "real" spec at the moment (they're listed as being documented in the "living standard", but that's not really the same). See: https://github.com/purescript-web/purescript-dom#non-standards-compliant-interfaces

We perhaps could start another purescript-web-nonstandard library or something to accommodate this kind of thing, and add an additional / new effect to track the usage of these kind of things.