[jdk8u-dev] RFR: 8287011: Improve container information

[Jonathan Dowland]

Low-risk backport for Oracle parity. Improves diagnostic output for humans. Not quite clean: path shuffling; comment copyright line adjustments; context issues as jdk8u lacks the pid controller (JDK-8266490)

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Depends on: https://git.openjdk.org/jdk8u-dev/pull/724

Commit messages:
 - 8287011: Improve container information

Changes: https://git.openjdk.org/jdk8u-dev/pull/725/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk8u-dev&pr=725&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8287011
  Stats: 127 lines in 9 files changed: 106 ins; 13 del; 8 mod
  Patch: https://git.openjdk.org/jdk8u-dev/pull/725.diff
  Fetch: git fetch https://git.openjdk.org/jdk8u-dev.git pull/725/head:pull/725

PR: https://git.openjdk.org/jdk8u-dev/pull/725