…ntersections.

Highways with a common name but different IDs occur when a boulevard is represented as two separate ways.
Clustered intersections occur when boulevards intersect. This results in a single "intersection," as a human would consider it, being represented by several way crossings. This is helpful for routing purposes, but not for user interactions.

Signed-off-by: Ted Steiner <tsteiner2@gmail.com>

I was getting errors on OS X.

Signed-off-by: Ted Steiner <tsteiner2@gmail.com>

Now when a highway is reduced to 0 length, it is deleted in the replaceHighwayNodes! function.
Now skip intersection consolidation when intersection has only one associated highway (ends of roads). This prevents the end of a boulevard (such as when cropped) from being joined together.
Removed unused clustered_highways variable.

Issue #31.

Signed-off-by: Ted Steiner <tsteiner2@gmail.com>

…IntersectionConsolidation

Pulling in minor bug fix for plotMap.

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Now if a highway has been removed from highways but still exists in the roadways classifier, it will simply be skipped during highway segmentation.
Previously this resulted in a key not found error.

Signed-off-by: Ted Steiner <tsteiner2@gmail.com>

Changed type HighwayCluster to HighwaySet.
Intersection clustering requires nodes to be in ENU coordinates.

Issue #31.

Signed-off-by: Ted Steiner <tsteiner2@gmail.com>

…documentation.

The list of cluster IDs is no longer returned, since it can easily can be extracted from the intersection ID to cluster ID mapping dictionary.

Issue #31

Signed-off-by: Ted Steiner <tsteiner2@gmail.com>

Signed-off-by: Ted Steiner <tsteiner2@gmail.com>