[OSIS-3444] save search type in session
[OSIS-3444] save search type in session

	modified:   base/views/learning_units/search/common.py

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