In compute-intersection.sh, keep 4 last working directories for each country
In this piece of code
work_dir=$work_base_dir/$(date +%Y-%m-%d-%H-%M-%S)/$country/$tm_project/
mkdir -p $work_dir
echo ------------------------------------------------------
echo Clean oldest working dirs, keep only the 4 newest ones.
echo
ls -1trd $work_base_dir/* | head -n -4 | xargs rm -rf