OSIS-639 Extracted method extract specific data from form cleaned data
OSIS-639 Extracted method extract specific data from form cleaned data

One method to extract entities form form data
and the other one to extract form data specific to attributes
of learning unit

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