OSIS-799 Refactor _proposal_management to lower complexity
OSIS-799 Refactor _proposal_management to lower complexity

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