To function `plot_single_traj`.

To function `plot_single_traj`.

Instead of storing it in the repository.

This should have been removed in commit 311c0598.

Remove timings from inside function `create_traj_list`.

Move function `create_traj_list` to a separate file.

Preparing for an independent script.

This should have been changed in commit 122b78b6.

Not worth it any longer. The function was introduced in commit
480800c9, when it had more to do.

Separate the construction of `traj_vert_ind` and the definition of
`traj_prop`. The motivation is to be able to create the files
`*traj*.json` for only a component of the graph, so that
`plot_traj.py` can plot the trajectories in a single component, with
different colors for different trajectories. A side benefit is that
the script `trajectories.py` becomes clearer. I have measured on the
global graph for 1993-2023 that this modification does not make a
significant change on the running time of the script.

This is useful to go from vertex to trajectory. For example, Artemis
wants to find the duration of the trajectory before each merging.

This was not useful since we do not need an array of snapshots in
`inst_eddies`. It is clearer without the integration in a snapshot
variable. The integration in a snapshot variable came from initial
commit, when there was only one program for detection of instantaneous
eddies and overlapping.

Ask for option `-assume noold_maxminloc` of Intel compiler. Without
this option, in procedure `set_max_speed`, if the speed values of all
the contours are NaN then the compiler wrongly sets `i` to 1 instead
of 0 at line 142, so `max_speed` is set to NaN instead of
`missing_speed` and the speed contour is wrong.

Replace argument `s` of `write_snapshot` by its component `list`.

Replace argument `s` of `set_all_extr` by its components. The idea is
to remove the structure `snapshot` from program `inst_edddies`.

We are circumventing a bug of the Intel Fortran compiler. This was
tested with both ifx `2023.1.0` and ifort `2021.9.0`. The bug occurs
on return from procedure `set_max_speed`: `free(): double free
detected in tcache 2` and crashes execution. The bug is revealed in
commit cc13fd5b. The GNU compiler does not have this bug.

To circumvent the Intel compiler bug, instead of an ssh component of
`cont_list_proj`, we have to use a separate array:
`cont_list_ssh`. This is maybe for the best because the component
`area` of `cont_list_proj` was not defined.

`n_points` can be deduced from previous print, and `n_extr` has been
printed too.

If `l != 0` then `shape_rec.record.r_eq_area >= 0` so `n_points` was
always equal to `n_points_valid`: no need for a separate variable.

Because the loop on shapes may take long.

`MAX_RADIUS_deg` is not general enough for a non longitude latitude
grid. The variable `max_radius` moves from module `input_ssh_m` to
module `config_m`. The variable `MAX_RADIUS_deg` disappears. The
constraint `2 * max_radius_deg(1) < 180` becomes `4 * max_radius(1) <
nlon` but is only applied to the periodic case because we do not have
the general equivalent of 180° in number of points.