Take Paul Tol's color schemes seriously

[tecosaur]

1. The following missing Tol colour schemes are added:

   • high-contrast (as tol_highcontrast, qualitative)
   • medium-contrast (as tol_medcontrast, qualitative)
   • vibrant (as tol_vibrant, qualitative)
   • nightfall (as tol_nightfall, continuous)
   • incandescent (as tol_incandescent, continuous)

2. The ordering of the qualitative color schemes is updated to match the ordering recommended on Paul Tol's website in this section:

3. The incorrect second colour in the iridescent colour scheme is corrected (#FCF705 -> #FCF7D5).

4. Remove #DDDDDD as the final entry of tol_muted. It is not part of the colour scheme but the "bad data" colour for the scheme. No other colour scheme with a "bad data" colour has it as part of the scheme.

5. A consistent naming scheme (tol_SCHEME) is also enforced, instead of having every second tol colour scheme follow different pattern.

Tol produces two variants on Colorbrewer schemes, which are both named inconsistently with Colorbrewer in different ways.

• tol_bu_rd -> tol_BuRd
• tol_prgn -> tol_PRGn

Tol's AVHRR global land cover classification scheme is incorrectly called "groundcover" and skips the "tol" prefix.

• ground_cover -> tol_land_cover

Similarly, Tol's iridescent scheme is missing the "tol_" prefix.

• Iridescent -> tol_iridescent

All four of these changes have duplicate entries created under the original name to preserve compatibility.

6. The colour scheme tol_ylorbr is registered separately but identically to tol_YlOrBr.

[codecov[bot]]

Codecov Report

Base: 74.35% // Head: 74.35% // No change to project coverage :thumbsup:

Coverage data is based on head (085c6cd) compared to base (24a5153). Patch has no changes to coverable lines.

Additional details and impacted files

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[cormullion]

Thanks!