RFR: 8129: Add tool to simplify platform upgrades

[Marcus Hirt]

Getting the versions needed from the eclipse update site. Can make something more out of this at a later point.

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Commit messages:
 - Copyright and import cleanup
 - 8129: Add tool to simplify platform upgrades

Changes: https://git.openjdk.org/jmc/pull/524/files
 Webrev: https://webrevs.openjdk.org/?repo=jmc&pr=524&range=00
  Issue: https://bugs.openjdk.org/browse/JMC-8129
  Stats: 142 lines in 3 files changed: 142 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jmc/pull/524.diff
  Fetch: git fetch https://git.openjdk.org/jmc.git pull/524/head:pull/524

PR: https://git.openjdk.org/jmc/pull/524