Dictionary instead of list, following update of `test_compare.py`.

Because stat is a module from Python standard library.

Use test `Region_5_15_days` instead of outside experiment `Inst_eddies_4`.

Rename test `Plot_eddy_contours_wind` to
`Plot_eddy_contours_window`. `wind` is misleading.

Changing my mind. In an SHPC, store shapefiles in
"Slice_{slice}/{orientation}" instead of
"{orientation}/Slice_{slice}". Two reasons: easier to store accessory
files from running `inst_eddies`, such as `perf_report` and output
from Torque submission script; clearer that a slice should contain the
same dates for both orientations.

Assume that a slice is in a directory
"{shpc_dir}/{orientation}/Slice_{slice}" where shpc_dir can be any
name, orientation is "Anticyclones" or "Cyclones" and slice is an
integer. Do not read or create any longer a file "orientation.txt" in
the slice directory. Add procedure `get_slice_dir`. Add dummy
arguments cyclone and slice to procedure `shpc_open`. Add dummy
argument slice to procedure `shpc_create`.

Move tests `Plot_eddy_contours_Mat` and `Stats_Matlab` to
`Convert_Matlab/Tests/long_tests.json`. Thus, we group the tests that
depend on the availability of Matlab.

Following update of `test_compare.py`.

This `accept.py` also serves as an example for a module accept
accompanying the script `filter.py`.

And it is then conveninent to choose it from the command line.

The script `plot_eddy_contours.py` was becoming too complicated.

Replace `SHPC_(anti|cyclo)_all_dates` by `SHPC_(anti|cyclo)`.

This SHPC was made with an old version of `inst_eddies`: it contained
cyclones and anticyclones output together. We create a test `Region_6`
instead.

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

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.

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

Run it with two dates and the new input NetCDF files. Two dates so it
can replace the SHPC that was in `$src_dir/Tests/Eddies_region_4`.

Instead of `$src_dir/Tests/Eddies_region_4`. Because
`$src_dir/Tests/Eddies_region_4` was made with an old version of
`inst_eddies`: cyclones and anticyclones output together.

Since it is a test on script which is in Analysis.

Move `Overlap/Tests/Input/Region_4/Eddies_region_4` to Tests. Now used
both in `Inst_eddies` and `Overlap`.

Move the creation of animation to new script
`anim_eddy_contours.py`. `plot_eddy_contours.py` was becoming too
complex. Some of the options of `plot_eddy_contours.py` did not apply
to the animation. Plus we now want to iterate in
`plot_eddy_contours.py` on cyclones and anticyclones so we are going
to have to add complexity in `plot_eddy_contours.py`.

From directory Analysis. Extract corresponding tests from
`Analysis/tests.json` into new file `Inst_eddies/Analysis/tests.json`.