Proposed Draft UTS #61, Unicode Set Notation

[markusicu]

FYI from UTC land: This is to “Inform ICU4X-TC of the PD UTS #‌61.”

@eggrobin authored https://www.unicode.org/review/pri523/ --> https://www.unicode.org/reports/tr61/tr61-1.html

by comparing several UnicodeSet specs and implementations, including “the ICU4X experimental implementation used in the experimental transliterator module”.

I am not sure if there is something specific to do for ICU4X at the moment. Robin has more information :-)

@sffc @robertbastian FYI