Add link between mandates and sectors when the data file is imported.
Add link between mandates and sectors when the data file is imported.

uclouvain/osis,uclouvain/osis_louvain,uclouvain/osis_louvain,uclouvain/OSIS-Louvain,uclouvain/osis,uclouvain/osis,uclouvain/OSIS-Louvain,uclouvain/osis_louvain,uclouvain/osis,uclouvain/OSIS-Louvain