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Released on September 2nd 2013.
- Auto scale tracks in distance calculation if needed (the metrics in
`wiggelen.distance` are not defined on the (0, 1) interval).
- Add min,posmin,max fields to track index.
- Optionally consider edges in `wiggelen.fill` (`only_edges` argument).
- Introduce the `plot` module for visualizing tracks.
- Rename command line ``visualize`` function to ``plot``.