Add support to mask/reveal/hide by polygons

[tpoisot]

Closes #231

[github-actions]

Documentation for this PR at https://poisotlab.github.io/SpeciesDistributionToolkit.jl/previews/PR263/

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 0% with 42 lines in your changes missing coverage. Please review.

Project coverage is 53.81%. Comparing base (7caf2b1) to head (4b9be6f).
Report is 18 commits behind head on main.

Files with missing lines	Patch %	Lines
src/polygons.jl	0.00%	37 Missing ⚠️
src/integrations/makie.jl	0.00%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #263      +/-   ##
==========================================
+ Coverage   52.71%   53.81%   +1.10%     
==========================================
  Files          59       59              
  Lines        1713     1546     -167     
==========================================
- Hits          903      832      -71     
+ Misses        810      714      -96     

Flag	Coverage Δ
unittests	53.81% <0.00%> (+1.10%)	⬆️

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[tpoisot]

So the proof of concept is working, now this needs to fully respect the GeoJSON spec - this means holes and multipolygons