RFR: 7831: Add new view for hierarchical edge bundling [v15]

[Brice Dutheil]

> Joint effort with @cimi to provide _hierarchical edge_ visualization to JMC.
> 
> ![Hierarchical Edge view](https://user-images.githubusercontent.com/803621/176186654-04f458f5-6f7d-4755-822c-f63e53ccfc31.png)
> 
> Here when the mouse hovers `java.util.concurrent` on the bottom right. One can see the relations with other packages.
> 
> 
> Based on the preliminary work of @cimi here : https://observablehq.com/@cimi/jfr-graph-hierarchical-edge-bundling

Brice Dutheil has updated the pull request incrementally with two additional commits since the last revision:

 - Set default package depth in dependency view to 2
 - Increase contrast on dependency view icons

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

Changes:
  - all: https://git.openjdk.org/jmc/pull/405/files
  - new: https://git.openjdk.org/jmc/pull/405/files/1ae425a5..41b08758

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jmc&pr=405&range=14
 - incr: https://webrevs.openjdk.org/?repo=jmc&pr=405&range=13-14

  Stats: 1 line in 5 files changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jmc/pull/405.diff
  Fetch: git fetch https://git.openjdk.org/jmc pull/405/head:pull/405

PR: https://git.openjdk.org/jmc/pull/405