* Bug: In Anabatic:
- In Dijkstra/Vertex, use the new Observer for fast access from the GCells.
- In Dijktra::propagate() loop detection.
- In Dijkstra, reset the "_from" of vertexes between two propagates on
the same Net (otherwise: loops...).
- In Matrix, there must be two different way of calculating an index from
a position. One for the min, which is rounded to superior. And one for
the max which is rounded to inferior.
- In Matrix::updateArea(), checks for invalid indexes.
* Bug: In Anabatic:
- In Edge, materialize was done before the Edge get it's final position.
Must be invalidated afterwards for the UpdateSession to put him in
the correct QuadTree.
- Functional (debugged) Dijkstra skeleton.