RFR: CODETOOLS-7902968: jcstress: Rework jcstress-samples

[Aleksey Shipilev]

jcstress-samples are in the dire need of rework: we can show more stuff about JMM, make sure it works with different JDKs, and that it produces interesting results most of the time.

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Commit messages:
 - CODETOOLS-7902968: jcstress: Rework jcstress-samples

Changes: https://git.openjdk.java.net/jcstress/pull/72/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jcstress&pr=72&range=00
  Issue: https://bugs.openjdk.java.net/browse/CODETOOLS-7902968
  Stats: 6849 lines in 53 files changed: 4833 ins; 2009 del; 7 mod
  Patch: https://git.openjdk.java.net/jcstress/pull/72.diff
  Fetch: git fetch https://git.openjdk.java.net/jcstress pull/72/head:pull/72

PR: https://git.openjdk.java.net/jcstress/pull/72