Motivation: being able to choose a different output format at
run-time. We use the graphml format for the automated test, because
graphml is a text format, so we can compare the results of two runs.

To be able to read edgelists output by the Fortran program.

They had the default values.

Remove unused `e_overestim`, `d_init`, `orientation`.

Use `comp_ishape` and `open_shpc` from `util_eddies`.

Do not store in memory all the records from shapefile
`max_speed_contour`.

But we should find some way not to impose a directory structure to the
user.

We do not want hard-coded paths in the script.

We do not want to change the script to change orientation.

Assume that `node_id_param.json` is in the current directory. We do
not want paths written inside the script.

With no `d_init` argument. In the returned value, we use key
`date_index` instead of `days_1950`.

Following update of `test_compare.py`.