RFR: CODETOOLS-7903176: Move LJV inside JOL [v3]

[Ivan Ponomarev]

> This moves https://github.com/atp-mipt/ljv project inside JOL in order for LJV to get access to internal JOL's APIs.
> 
> See blogposts about LJV [in Russian](https://habr.com/ru/post/599045/) /  [in English](https://dzone.com/articles/what-can-we-learn-from-java-data-structures-visual).

Ivan Ponomarev has updated the pull request incrementally with one additional commit since the last revision:

  minor changes (#5)
  
  * HashCodeCollision reimplementation
  * JDK headers fix
  *  LJV Github actions removed
  * other code review fixes
  
  Co-authored-by: Ivan Ponomarev <iponomarev at mail.ru>

-------------

Changes:
  - all: https://git.openjdk.org/jol/pull/24/files
  - new: https://git.openjdk.org/jol/pull/24/files/5001f98d..3a9feff0

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jol&pr=24&range=02
 - incr: https://webrevs.openjdk.org/?repo=jol&pr=24&range=01-02

  Stats: 502 lines in 40 files changed: 371 ins; 68 del; 63 mod
  Patch: https://git.openjdk.org/jol/pull/24.diff
  Fetch: git fetch https://git.openjdk.org/jol pull/24/head:pull/24

PR: https://git.openjdk.org/jol/pull/24