Removed more print statements
:(
Fixed problem when comparing points to empty geometries
Added linked list implementation

Make life a bit easier when building linestrings/polygons
Added utility accessors

Added forwardLabels and backwardLabels to Graph.
There was too much of the forwardEdge.map((e) => e.label) going on for
my liking
Geometry lists are now emty if every element is empty

Previous it was any, which was obviously wrong
Add linked list tests to all tests