Log Message:
update to 4.2.1
major changes:
Locale Data: ICU uses and supports data from Common Locale Data Repository
(CLDR) 1.7 , which includes data for 146 languages, 159 territories,
468 locales- 21% more locale data than the previous release.
Number system support and the number keyword.
Number system override in DateFormat
Numerics used by Hebrew Calendar date in Hebrew locale
BCP47 (language tag) / Locale transformation
BCP47 mapping of LDML keywords
Encoding selector: Return a list of charsets that can handle the input text
Simple duration: Implementation of CLDR duration format
Available/Preferred keywords for a locale (Calendar, Collation, and Currency)
StringPrep standard profiles: RFC3491 NAMEPREP, RFC3530 NFS4, RFC3722 iSCSI,
RFC3920 NodePrep/ResourcePrep, RFC4011 MIB, RFC4013 SASLprep, RFC4505 trace
and RFC4518 LDAPprep
Miscellaneous Arabic shaping enhancements
UTF-8 friendly internal data structure for Unicode data lookup
API to get CLDR version used by ICU
ISCII charset converter updates (added Gurumukhi, other updates)
Performance improvements in Time Zone Name format/parse, and in
DateIntervalFormat construction