RFR: 8247781: Day periods support

[Naoto Sato]

Hi,

Please review the changes for the subject issue. This is to enhance the java.time package to support day periods, such as "in the morning", defined in CLDR. It will add a new pattern character 'B' and its supporting builder method. The motivation and its spec are in this CSR:

https://bugs.openjdk.java.net/browse/JDK-8254629

Naoto

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Commit messages:
 - 8247781: Day periods support

Changes: https://git.openjdk.java.net/jdk/pull/938/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=938&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8247781
  Stats: 1022 lines in 17 files changed: 838 ins; 87 del; 97 mod
  Patch: https://git.openjdk.java.net/jdk/pull/938.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/938/head:pull/938

PR: https://git.openjdk.java.net/jdk/pull/938