[code-reflection] Integrated: HAT shade buildout

[Gary Frost]

Shade needs fvec2,3,4  and ivec2 types. So experimenting with adding them to Uniform list .

Also discovered that Panama/memorySegments are actually pretty efficient when holding RasterData types (for copying to ImageBuffers)

To prove the case I added an 'OpenGL free' nbody variant (curently in the shade-experiment code) 

JARS=build/hat-optkl-1.0.jar:build/hat-core-1.0.jar
JARS=${JARS}:build/hat-backend-ffi-shared-1.0.jar:build/hat-backend-ffi-opencl-1.0.jar
JARS=${JARS}:build/hat-example-shade-1.0.jar
java --add-modules=jdk.incubator.code --enable-native-access=ALL-UNNAMED -cp ${JARS} -Djava.library.path=./build \
   shade/NBodySansGL HAT &
java --add-modules=jdk.incubator.code --enable-native-access=ALL-UNNAMED -cp ${JARS} -Djava.library.path=./build \
   shade/NBodySansGL JavaSeq &
java --add-modules=jdk.incubator.code --enable-native-access=ALL-UNNAMED -cp ${JARS} -Djava.library.path=./build \
   shade/NBodySansGL JavaMT &

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Commit messages:
 - Add copyright
 - Separate vec implementations from Uniforms and NBodyNoGL
 - cleaning up uniform types

Changes: https://git.openjdk.org/babylon/pull/888/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=888&range=00
  Stats: 891 lines in 13 files changed: 813 ins; 12 del; 66 mod
  Patch: https://git.openjdk.org/babylon/pull/888.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/888/head:pull/888

PR: https://git.openjdk.org/babylon/pull/888