[code-reflection] Integrated: Hat sync jextract and hat nbody and life demos

[Gary Frost]

Trying to merge the jextract and HAT versions of game of life (and nbody) into single version.

This is step 1.

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Commit messages:
 - whitespace
 - nbody and life demos now allow jextract and hat versions

Changes: https://git.openjdk.org/babylon/pull/336/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=336&range=00
  Stats: 2778 lines in 22 files changed: 564 ins; 1902 del; 312 mod
  Patch: https://git.openjdk.org/babylon/pull/336.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/336/head:pull/336

PR: https://git.openjdk.org/babylon/pull/336