[D&D] Add support for release as beta/preview feature

[joshuarrrr]

Core Requirement:

• Add a flag in the YAML config to enable and disable the D&D plugin #1877

Other exit criteria (Needs to be finalized):

• Add experimental banner on top of D&D editor to warn users and link to github to create issues (similar to the control visualization) #1892
• Use advanced setting visualize:enableLabs to enable and disable D&D #1893
• [D&D] Provide link to experimental feature feedback forum/poll/issue #1962

[ashwin-pc]

@ahopp Do these requirements make sense?

[joshuarrrr]

The existing code makes distinctions between beta and experimental visualizations, which mostly affect the language used:

Beta

Message:

This visualization is in beta and is subject to change. The design and code is less mature than official GA features and is being provided as-is with no warranties. Beta features are not subject to the support SLA of official GA features

via

• new visualization selector
• visualization listing

Experimental

New visualization message:

This visualization is experimental. The design and implementation are less mature than stable visualizations and might be subject to change.

via:

• new visualization selector

New visualization tooltip:

This visualization might be changed or removed in a future release and is not subject to the support SLA.

via:

• new visualization selector
• visualization listing

Banner message:

This visualization is experimental and is not subject to the support SLA of official GA features.
For feedback, please create an issue in {githubLink}."

via:

• ExperimentalVisInfo

@ahopp @kgcreative Can we get some updates for this language, both for general purpose use and for the experimental case we're using for D&D?