OSIS-4064 fixed blank choice of 'end year' to create a program tree version
OSIS-4064 fixed blank choice of 'end year' to create a program tree version

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