All of these algorithm implementations already existed, but I'm
proposing a new way to organize them which I hope will be more
consistent and discoverable.

Note: The new Haversine::bearing and Geodesic::bearing return 0..360,
the legacy traits HaversineBearing and GeodesicBearing returned
-180..180

Additional changes:

Deleted the deprecated `Bearing` trait which was previously superceeded
by the unambiguous `HaversineBearing` trait, but now is re-defined as
`Haversine::bearing`

= Future Work =

In an effort to minimize this PR, while keeping the change reasonably
coherent, I've left some things out

== Methods on Euclidean ==
 -[ ] bearing (doesn't currently exist)
 -[ ] destination (doesn't currently exist)
 -[ ] intermediate (exists, but InterpolatePoint trait also needs intermediate_fill)
 -[ ] intermediate_fill (doesn't currently exist)

== Deprecate Legacy Traits ==
 -[ ] Deprecate Legacy impls
 -[ ] Switcheroo the actual implementation: move the actual implementation to the new traits, and have the legacy traits delegate to the new traits.
 -[ ] Move over any tests from the legacy implementation to the new home

== Methods on Geoms (Future PR) ==
 -[ ] Length
     -[ ] Haversine
     -[ ] Rhumb
     -[ ] Geodesic
     -[ ] Euclidean
 -[ ] Densify
     -[ ] Haversine
     -[ ] Rhumb
     -[ ] Geodesic
     -[ ] Euclidean

FIXES #1210
FIXES #1181

This is needed for the "Unify line measures" work.

This was a copy/paste error from the impl on Geodesic which truly does
only support f64 - for Haversine and Rhumb though, we can support any
CoordFloat+FromPrimitive