Added edge starring to graph

Now possible to control the sorting of edges around a node
Geometry.dispatchToType got a whole lot more comprehensive
ATTRIBUTIONS is now a markdown file
Added edge sorting to graph
Implemented edge starring in geomgraph
Added in tests for edge sorting.

Still one failing unit test
IntersectionMatrix tests now use Lists instead of Arrays
Implemented Linestring builder

I don't know why, but I'm not really enthusiastic about implementing
overlays, which motivated me to redo the graph stuff.

I don't see why, this is what I've been working towards most of the year