Demo rfc80 density plot

[uklineale]

Fix # (see https://help.github.com/en/articles/closing-issues-using-keywords)

Describe changes proposed in this pull request:

• Use clickhouse for density plot calls
• Refactor logic into service to clean up controller
• Simplify logic into Java streams

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[haynescd]

LGTM

[haynescd]

Great Job @uklineale