[tlbuild] Upcoming ICU 66 release

[Nelson H. F. Beebe]

The release dates for the upcoming ICU 66 (International Components
for Unicode) release are close to the TeX Live 2020 code freeze, but
some list members may nevertheless wish to install the ICU 66
prerelease to find out if there are more show stoppers for TeX Live.
Here is mildly-reformatted text from the Unicode mailing list posted
yesterday afternoon (Thu, 5 Dec 2019):

>> ...
>> Dear Unicoders,
>>
>> If you use ICU, then testing with ICU 66*preview*
>>
>> 	http://site.icu-project.org/download/66
>>
>> is a good way of trying out Unicode 13 *beta*
>>
>> 	http://blog.unicode.org/2019/11/unicode-130-beta-review.html
>>
>> ...
>>
>> Dear friends and users of ICU,
>>
>> We are pleased to announce a preview of ICU 66. ICU 66 (scheduled for
>> release in 2020 March) will update to Unicode 13, and include some bug
>> fixes. This will be a low-impact release with no other significant feature
>> additions or implementation changes.
>>
>> ICU 66preview updates to Unicode 13 beta
>>
>> 	http://blog.unicode.org/2019/11/unicode-130-beta-review.html
>>
>> including new characters, scripts, emoji, and corresponding API
>> constants. It also updates to CLDR 36.1preview
>>
>> 	http://cldr.unicode.org/index/downloads/cldr-36
>>
>> with Unicode 13 updates and bug fixes. For details please see
>>
>> 	http://site.icu-project.org/download/66
>>
>> Please test this preview on your platforms and report bugs and regressions
>> by Tuesday, 2020-jan-07.
>>
>> Please do not use this preview in production.
>>
>> The preliminary API reference documents are published on
>>
>> 	http://unicode-org.github.io/icu-docs/
>>
>> follow the Dev links there.
>>
>> Best regards,
>>
>> Markus Scherer for the ICU Project
>> ...

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- Nelson H. F. Beebe                    Tel: +1 801 581 5254                  -
- University of Utah                    FAX: +1 801 581 4148                  -
- Department of Mathematics, 110 LCB    Internet e-mail: beebe at math.utah.edu  -
- 155 S 1400 E RM 233                       beebe at acm.org  beebe at computer.org -
- Salt Lake City, UT 84112-0090, USA    URL: http://www.math.utah.edu/~beebe/ -
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