[code-reflection] Integrated: Hat cleanup heal example

[Gary Frost]

HealingBrush demo cleaned up. 

Removed some classes and merged others.

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Commit messages:
 - Merge Display and Viewer
 - Remove ImageData (replace with S32Array2D)
 - Heal cleanup combine XYList and RGBList
 - Heal cleanup remove unused classes Path->Selection
 - Heal cleanup remove unused classes

Changes: https://git.openjdk.org/babylon/pull/206/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=206&range=00
  Stats: 2386 lines in 20 files changed: 641 ins; 1720 del; 25 mod
  Patch: https://git.openjdk.org/babylon/pull/206.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/206/head:pull/206

PR: https://git.openjdk.org/babylon/pull/206