RFR: 7903779: unify logger messages to show position whenever possible [v2]

[Athijegannathan Sundararajan]

> * logger.warn/.err/.info Position accepting overloads.
> * Error message format is: <position>:"fatal"|"error"|"warning"|"info"|:<message> (consistent with clang).
> * ClangException has position, severity and spelling. ClangExceptions are printed using logger.print.

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

  moved PositionRecord to the method where it is used (review comment)

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Changes:
  - all: https://git.openjdk.org/jextract/pull/254/files
  - new: https://git.openjdk.org/jextract/pull/254/files/3fe7c65e..a062d16b

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jextract&pr=254&range=01
 - incr: https://webrevs.openjdk.org/?repo=jextract&pr=254&range=00-01

  Stats: 4 lines in 1 file changed: 2 ins; 2 del; 0 mod
  Patch: https://git.openjdk.org/jextract/pull/254.diff
  Fetch: git fetch https://git.openjdk.org/jextract.git pull/254/head:pull/254

PR: https://git.openjdk.org/jextract/pull/254