[PATCH] Make Unicode generation reproducible.

[Florian Weimer]

* Carlos O'Donell:

> diff --git a/localedata/unicode-gen/UnicodeRelease.txt b/localedata/unicode-gen/UnicodeRelease.txt
> new file mode 100644
> index 0000000000..bd9cc14ae0
> --- /dev/null
> +++ b/localedata/unicode-gen/UnicodeRelease.txt
> @@ -0,0 +1,8 @@
> +% This metadata is used by glibc and updated by the developer(s)
> +% carrying out the Unicode update.
> +Version,13.0.0
> +ReleaseDate,2021-03-10
> +Data,UnicodeData.txt
> +DcpData,DerivedCoreProperties.txt
> +EawData,EastAsianWidth.txt
> +PlData,PropList.txt

I suggest to use <https://www.unicode.org/Public/13.0.0/ucd/ReadMe.txt>
instead.  It would give 2020-03-06 as the date.  2021-03-10 is
definitely wrong, it should be 2020-03-10.

Perhaps it's time to move the *.txt files into their own directory and
also include <https://www.unicode.org/copyright.html> and
<https://www.unicode.org/license.html>.

Thanks,
Florian