Add LineStringSegmentizeHaversine

[JosiahParry]

• [x] I agree to follow the project's code of conduct.

• [x] I added an entry to CHANGES.md if knowledge of this change could be valuable to users.

Supercedes https://github.com/georust/geo/pull/1106.

This PR:

• adds a new trait LineStringSegmentizeHaversine to segment a linestring using haversine distance instead of euclidean distance
  • this gives downstream users an option to segment linestrings on geographic as well as projected coordinates
• fixes a bug in LineStringSegmentize where n - 1 linestrings were created for very small distances
  • this was caused by precision in the 6-ish decimal place. It was fixed by subtracting f64::EPSILON from the calculated segment length that is passed to densify()
• turns the segmentize implementation into a macro.
  • the benefit of this is that segmentize for haversine does not need to duplicate code and other future implementations (hopefully geodesic) will not need more than a Densify and Length trait of the same type.

[JosiahParry]

Please let me know if this needs any additional work. :)

[JosiahParry]

thanks for your help getting this across the line! Thank you!