Change all the places that were including the deprecated parser, to
include the new one instead, and then delete the old parser code.
`ParentNode::query_selector[_all]()` now treat their input as a
comma-separated list of selectors, instead of just one, and return
elements that match any of the selectors in that list. This is according
to these specs:
- querySelector/querySelectorAll:
https://dom.spec.whatwg.org/#ref-for-dom-parentnode-queryselector%E2%91%A0
- selector matching algorithm:
https://www.w3.org/TR/selectors-4/#match-against-tree
SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *