<i18n dev> RFR: 8303917: Update ISO 639 language codes table

[Justin Lu]

This PR modifies `java.util.LocaleISOData.isoLanguageTable` to include (name only) changes from up-to-date [ISO 639 data](http://www.loc.gov/standards/iso639-2/php/code_list.php.).

In addition, this PR updates the ISO 639 data (generated in 1999) in `Bug4175998Test.java`. This includes modifying the `generate_Tables() `function, since the source data is now stored in a different format. The outdated raw data stored in the bottom of the file was removed.

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Commit messages:
 - Minor changes / cleanup
 - Update ISO 639 test data
 - NC updates, revert Moldavian change
 - 2009-09-01 Name Change
 -  2008-11-03: Deprecate Moldavian/mo/mol

Changes: https://git.openjdk.org/jdk/pull/12980/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=12980&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8303917
  Stats: 843 lines in 2 files changed: 64 ins; 626 del; 153 mod
  Patch: https://git.openjdk.org/jdk/pull/12980.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12980/head:pull/12980

PR: https://git.openjdk.org/jdk/pull/12980