RFR: 8311653: Modify -XshowSettings launcher behavior

[Sean Coffey]

Modify the -XshowSettings launcher option to print non-verbose settings details of all components by default. Verbose settings details will be printed via the -XshowSettings:all option. Modify the -XshowSettings option to reject bad values passed to it. Print an error message in such scenarios and abort the VM launch.

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Commit messages:
 - restore imports
 - Abort if bad options input
 - 8311653

Changes: https://git.openjdk.org/jdk/pull/15001/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=15001&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8311653
  Stats: 142 lines in 4 files changed: 72 ins; 35 del; 35 mod
  Patch: https://git.openjdk.org/jdk/pull/15001.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/15001/head:pull/15001

PR: https://git.openjdk.org/jdk/pull/15001