RFR: 7903187: jextract should support --version option [v2]

[Athijegannathan Sundararajan]

> added --version option that prints the underlying Java version and exits.

Athijegannathan Sundararajan has updated the pull request incrementally with one additional commit since the last revision:

  adding more info to version output per review recommendation

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Changes:
  - all: https://git.openjdk.java.net/jextract/pull/31/files
  - new: https://git.openjdk.java.net/jextract/pull/31/files/d50cf947..a89d1937

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jextract&pr=31&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jextract&pr=31&range=00-01

  Stats: 4 lines in 1 file changed: 3 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jextract/pull/31.diff
  Fetch: git fetch https://git.openjdk.java.net/jextract pull/31/head:pull/31

PR: https://git.openjdk.java.net/jextract/pull/31