Starting to position the hexes on the sphere. Swim is returning somewhat inaccurate longitudes for some reason.
I am a moron.
Added arc interpolation and midpoint functions.
Added pentagon and edge interpolation. `swim` function isn't reliable for certain tests, but `course` appears to be accurate and equivalent for testing.
Added face field interpolation.
Fixed NaN positions and testing for them going forward. Adjusted test verbiage. Removed obsolete `link-edges` module.
Populating positions by default. Reformatted for style. Removed `swim`, replaced with the universally accurate `course`.
Merge pull request #3 from G-E-O-F/positions

Branch for determining spherical coordinates for the fields’ barycenters is appropriate for merging.