[GEOS-11324] MapML vector style classes

[turingtestfail]

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[aaime]

@prushforth this PR attempts to translate SLDs into CSS and apply it to the geometries, however, for what I've tried, we have little to play with. Basic line styles are working, the color of point symbolizes goes through, but for example the fill of polygon does not seem to be applied, and using fill or background-color does not seem to make a difference.

To test, set a layer in "features" mode, without tiling.

Do you have a list of CSS properties the client can work with?

[prushforth]

Do you have a list of CSS properties the client can work with?

Not really - we are copying classes from the map-feature onto the svg \ and child \ that renders it, and including styles in the preceding sibling element as actual \