RFR: 8253909: Implement detailed map file for CDS [v2]

[Ioi Lam]

> For analyzing the contents of a CDS archive, we need a "map file" that describes the archive in different levels of
> detail. This can be done using unified logging. E.g.,
> java -Xshare:dump -Xlog:cds+map=trace:file=cds.map:none:filesize=0
> 
> For example, we can use the map file for troubleshooting [JDK-8253495](https://bugs.openjdk.java.net/browse/JDK-8253495)
> (runtime/cds/DeterministicDump.java broken). We can diff two different cds.map files to see where the non-deterministic
> contents come from.
> See attachments in [JDK-8253909](https://bugs.openjdk.java.net/browse/JDK-8253909) for example map files at the
> info/debug/trace levels.

Ioi Lam has updated the pull request incrementally with one additional commit since the last revision:

  Feedback from Thomas Stuefe

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/474/files
  - new: https://git.openjdk.java.net/jdk/pull/474/files/44ad4be3..5dc43c70

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=474&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=474&range=00-01

  Stats: 165 lines in 6 files changed: 97 ins; 37 del; 31 mod
  Patch: https://git.openjdk.java.net/jdk/pull/474.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/474/head:pull/474

PR: https://git.openjdk.java.net/jdk/pull/474