We now impose that all eddies in an SHPC have the same
orientation. Remove field `extr_cycl` from the derived type shpc and
add field cyclone to shpc. When reading an eddy, give it the
orientation of its SHPC. Add argument cyclone to procedure
`shpc_create`. Create a file `orientation.txt` in each SHPC. When
writing an eddy, check that its orientation matches that of the SHPC.

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

Do not specify the orientation as a command line argument of
`report_graph_int.py`. As in commit 292305e.

For test `Report_graph_cyclo`.

Do not specify the orientation as a command line argument of
`report_graph.py`. We are reverting commit 0ca2da8c because now
edgelists and SHPC for interpolated eddies are normally in separate
directories, and edgelist is normally just `edgelist.csv`.

We are reverting commit b926e1b7 because now there are two SHPC input
directories for visible eddies, two SHPC for interpolated eddies and
edgelists in differents directories for the two orientations. Handling
the command line arguments would be awkward.

This SHPC was made with an old version of `inst_eddies`: it contains
cyclones and anticyclones output together. We use
`$tests_old_dir/Extraction_eddies_region_2_noise/SHPC_anti_all_dates`
instead. See also commits 488d5c08 and 8ed324ff.

Make it 15 days long because we want to use it in place of
`Overlap/Tests/Input/Region_2_SHPC`.

Because variables in `grid_nml` should be all defined in the input file.

We are reverting commits 35fad1b7 and df2b397d because we want the
program `eddy_graph.sh` to read an SHPC containing a single
orientation.

Instead of hard-coding a value.

Instead of reading `extr_map.nc`, `ishape_last.txt` and shapefile
extremum. The problem was the consistency between `extr_map.nc` and
the two other files. `extr_map.nc` contains eddies with the two
orientations while extremum now contains a single orientation, with
eddies renumbered.

Since it is now possible to have one or more SHPC as arguments.

`NSODS_in.txt` and `non_successive_overlap_in.txt` were the only files
left in directory `Region_4`. Not enough files to justify a directory.

Instead of asking the user to define it. So ne no longer need the file
`read_snapshot_nml.txt` for programs `test_read_snapshot` and
`test_send_recv`: we can just supply the remaining data in the `input`
key of tests `Read_snapshot` and `Send_recv`.

This file is a left-over from commit b456b50e. It should have been
moved to Tests/Eddies_region_4 in commit 5e0e0deb and deleted in commit
8ed324ff.

This SHPC was made with an old version of `inst_eddies`: it contains
cyclones and anticyclones output together. We use
`$tests_old_dir/Inst_eddies_loop` instead. See also commit 8ed324ff.

Move the test `Inst_eddies_lopp` earlier in the test series because we
are going to use its results in subsequent tests.

Because we are going to use it in `test_nearby_extr`.

This is necessary since we now output separately cyclones and
anticyclones from `inst_eddies.`

This is more comfortable. Furthermore, it is going to be necessary
when we extend the script to several input SHPC.

For an animation, we want several dates so we need `ishape_last.txt`.

`make_animation` seems too general, the reader may think it is an
object of Matplotlib.

Write `SHPC*` instead of `SHP_triplet_*` directories.

Required since commit f9f99c4.

Since commit 8842ed2, the tests use
`$tests_old_dir/Extraction_eddies_region_4`, which contains two
SHPC. Just use one of them.

Rename `Region_1_SHP_triplet_noise` to `Region_1_SHPC_noise`.