RFR: 8400: Add more show options for JMX Console graphs

[Marcus Hirt]

Also cleaning up a little bit. There were some assumptions around the default XY chart that should be put in code etc.

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Commit messages:
 - Cleanup. Ensuring that the axis is responsible for bounds.
 - 8400: Add more show options for JMX Console graphs

Changes: https://git.openjdk.org/jmc/pull/652/files
  Webrev: https://webrevs.openjdk.org/?repo=jmc&pr=652&range=00
  Issue: https://bugs.openjdk.org/browse/JMC-8400
  Stats: 874 lines in 15 files changed: 692 ins; 55 del; 127 mod
  Patch: https://git.openjdk.org/jmc/pull/652.diff
  Fetch: git fetch https://git.openjdk.org/jmc.git pull/652/head:pull/652

PR: https://git.openjdk.org/jmc/pull/652