Line plotting doesn't deal well with map boundaries

This is an issue in basemap that can be seen with functions like [`drawgreatcircle`](https://matplotlib.org/basemap/api/basemap_api.html#mpl_toolkits.basemap.Basemap.drawgreatcircle) and [`tissot`](https://matplotlib.org/basemap/api/basemap_api.html#mpl_toolkits.basemap.Basemap.tissot). I think that most cases can be fixed with a smart `roll` of the line points.