[code-reflection] Integrated: Add SSA id dependency viewer tool + DotViewer infra

[Gary Frost]

Another HAT tool that I needed to find a home for. 

This one shows a dependency graph between the SSA id (refs to defs) for a given Babylon funcOp graph.

This is essentially a DOT graph view of the dependencies shown in the existing line based FuncOpViewer tool

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Commit messages:
 - Add SSA id dependency viewer tool + DotViewer infra

Changes: https://git.openjdk.org/babylon/pull/511/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=511&range=00
  Stats: 3346 lines in 25 files changed: 3259 ins; 42 del; 45 mod
  Patch: https://git.openjdk.org/babylon/pull/511.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/511/head:pull/511

PR: https://git.openjdk.org/babylon/pull/511