Add MET ASCII2NC supported datasets to verification datasets

[DanielAdriaansen]

Describe the Enhancement

When testing the UGRID capability, I noticed that here:
https://met.readthedocs.io/en/develop/Users_Guide/reformat_point.html#ascii2nc-tool

We describe various datasets that are supported by ASCII2NC. However, not all of them are documented here:
https://metplus.readthedocs.io/en/develop/Verification_Datasets/index.html

Notably:

1. AirNow
2. NBDC Buoy
3. IABP
4. SURFRAD

Seem to be absent from the "Verification Datasets" page. NBDC Buoy data were what I was using. Looking through old PR's, issues, and use cases, I see:

AirNow

dtcenter/MET#2314
dtcenter/MET#2373
(@JohnHalleyGotway and @davidalbo)

NBDC Buoy

dtcenter/MET#2294
#1908
(@j-opatz and @davidalbo)

IABP

dtcenter/MET#2846
(@JohnHalleyGotway and @davidalbo)

SURFRAD

dtcenter/MET#205
(@JohnHalleyGotway)

I'll create stubs in the documentation for each dataset, and coordinate with the above folks to curate the content on the page and/or review the content that I add.

Time Estimate

1 day

Relevant Deadlines

NONE.

Funding Source

Define the source of funding and account keys here or state NONE.

Define Related Issue(s)

Consider the impact to the other METplus components.

• METplus, MET, METdataio, METviewer, METexpress, METcalcpy, METplotpy

Enhancement Checklist

See the METplus Workflow for details.

• Complete the issue definition above, including the Time Estimate and Funding Source.
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• Close this issue.

[DanielAdriaansen]

Should also just do #2448 at the same time as this- touching the same code.

[DanielAdriaansen]

Working in branch feature_2568_vx_datasets_update.