Revisit regional dropdown and align with corpus

[pbuttigieg]

The terms in the drop down on the landing page (see figure) should pre-filter the corpus by 1) subsetting records that have geospatial coordinates within a set of OIH-defined GeoJSON shapes associated with each category and 2) subsetting records which have an schema.org address which includes a term associated with the region category in our UNSD-derived file.

• Assess whether regional categories and their associated GeoJSON files are representative of the corpus
  • Confirm whether the link to the UNSD administrative region classification is functioning as expected.
• Assess whether regions from marineregions.org or another provider (IHO regions?) can be used in addition to what we have
• Update shapefiles defining regions
• Update the UNSD file in our repo to include other regions (documenting clearly that these are not UNSD)
• Update regional selection
• Enable multi-select (xref Design and implement an Advanced Search option #48)