[jdk11u-dev] RFR: 8237354: Add option to jcmd to write a gzipped heap dump

[BuddyLiao]

Backport of the heap dump enhancement: Add option to jcmd to write a gzipped heap dump

Patch did not apply cleanly, I had to resolve/modify

src/hotspot/share/services/heapDumper.cpp
src/hotspot/share/services/heapDumperCompression.cpp
src/hotspot/share/services/heapDumperCompression.hpp

I have built it on linux x86_64 and run test-tier1

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Commit messages:
 - Backport 19be49714356f2f598924c9fefa6358679ab6dbe

Changes: https://git.openjdk.java.net/jdk11u-dev/pull/209/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk11u-dev&pr=209&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8237354
  Stats: 1758 lines in 13 files changed: 1638 ins; 52 del; 68 mod
  Patch: https://git.openjdk.java.net/jdk11u-dev/pull/209.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk11u-dev pull/209/head:pull/209

PR: https://git.openjdk.java.net/jdk11u-dev/pull/209