RFR: 8299576: Reimplement java.io.Bits using VarHandle access

[Per Minborg]

Currently, `java.io.Bits` is using explicit logic to read/write various primitive types to/from byte arrays. Switching to the use of `VarHandle` access would provide better performance and less code. 

Also, using a standard API for these conversions means future `VarHandle` improvements will benefit `Bits` too. 

Improvements in `Bits` will propagate to `ObjectInputStream`, `ObjectOutputStream` and `RandomAccessFile`.

Initial benchmarks and performance discussions can be found here: https://github.com/openjdk/panama-foreign/pull/762

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Commit messages:
 - Update copyright year to 2023
 - Update copyright year
 - Reimplement java.io.Bits using VarHandle access

Changes: https://git.openjdk.org/jdk/pull/11840/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11840&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8299576
  Stats: 463 lines in 2 files changed: 424 ins; 24 del; 15 mod
  Patch: https://git.openjdk.org/jdk/pull/11840.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11840/head:pull/11840

PR: https://git.openjdk.org/jdk/pull/11840