Use waypoints for smoother ways

[fbanning]

Currently all roads are comprised of multiple "unconnected" linesegments which just happen to end at the same position at which another linesegment starts. This leads to precise display of street corners and such. But this precision doesn't look so nice when there are sharp bends in a road and leads to whitespace which reveals that the linesegments aren't connected to each other.

GraphMakie provides the ability to pass waypoints to plot an edge, see https://juliaplots.org/GraphMakie.jl/stable/generated/plots/#Edge-waypoints . Using this functionality with a small r value could lead to nicer looking roads/edges with the underlying data on how their nodes are interconnected.