Following updates of the libraries.

Following updates of the libraries.

Note that programs `test_max_speed_contour_ssh` and `test_weight`
depend on fortranGIS through the module derived_types. Compilation
worked without linking to fortranGIS because objects used by
`test_max_speed_contour_ssh` and `test_weight` in
derived types do not use fortranGIS.

Instead of creating them. Motivation: avoid time spent concatenating
shapefiles in `inst_eddies.py`. This concatenation time, on Ciclad, is
of the same order of magnitude as the time spent by the Fortran
executable.

In case we are a sub-project.

Rename triplet to collection, `shp_tr` to shpc, shpt to shpc in
comments, identifiers and file names.

`read_eddy.f90`, `read_field_indices.f90` and `shp_tr_open.f90` will
become common to Overlap and `Inst_eddies` because they will be used
in `Inst_eddies/Tests/test_set_max_speed.f90`. So there are now enough
common files to justify a new directory.

Preparing for two collections of shapefiles. We create the
procedure `write_nml` so we will be able to call it twice. But it
needs to access the namelist. So the namelist must be at the module level.

Extract writing of `ishape_last.txt` and `grid_nml.txt` to new
procedure `write_aux`. Preparing for two collections of shapefiles.

Preparing for configuration of location of binary executable.

Following update of libraries: NetCDF-Fortran is private in NetCDF95
and MPI-Fortran is private in EZMPI.

Also split the tests, Fortran source files, Python files and JSon
files. Keep at the top level the files used in both `Inst_eddies` and
Overlap.

Motivations for the split:

- The top directory contained many files.

- It may be useful to compile only one of the two sub-projects. For
example, only `Inst_eddies` on Ciclad, where MPI 3 is not available.