RFR: 8276265: jcmd man page is outdated

[David Holmes]

It was noticed that a number of updates to the jcmd subcommands (some new, some modified) had not been added to the manpage. The text was supplied by @tstuefe - thanks Thomas. I applied the changes to the closed markdown sources and regenerated the nroff file. For easier review I have generated a html version that can be viewed here:

https://htmlpreview.github.io/https://github.com/dholmes-ora/jdk/blob/57c00815460ffef201239eafac322b4dd246da1b/jcmd.html

Summary of changes:

New Commands:
- Compiler.perfmap
- System.trim_native_heap
- VM.cds
- VM.classloaders
- VM.events
- VM.metaspace

Missing flags:
- GC.class_histogram -parallel
- GC.heap_dump - gz and overwrite options
- Thread.print -e

There are further improvements that could be made, some mentioned in the bug report. I also noticed a general confusion between arguments and options with some subcommands, but I did not try to address that.

Thanks,
David

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Commit messages:
 - Removed temporary addition of html version.
 - Temporary commit of html version
 - 8276265: jcmd man page is outdated

Changes: https://git.openjdk.java.net/jdk/pull/6271/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=6271&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8276265
  Stats: 153 lines in 1 file changed: 146 ins; 6 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/6271.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/6271/head:pull/6271

PR: https://git.openjdk.java.net/jdk/pull/6271