RFR: 8274413: FX: Update copyright year in docs, readme files to 2022

[Ambarish Rapte]

Copyright year in these 3 docs needs to be updated to 2022.

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Commit messages:
 - copyright year to 2022

Changes: https://git.openjdk.java.net/jfx/pull/645/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jfx&pr=645&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8274413
  Stats: 3 lines in 3 files changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.java.net/jfx/pull/645.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/645/head:pull/645

PR: https://git.openjdk.java.net/jfx/pull/645