Fixed disparities between jsdoc and function typedefs esp Units and GeoJsonProperties

[smallsaucepan]

Fixed disparities between jsdoc and function typedefs, mainly focused on Units and GeoJsonProperties. Also replaced a few more instances of Turf specific Id typedef, standardised wording of param descriptions (e.g. on Units, GeoJsonProperies), and updated example code to use const rather than var.

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