- parser update:
 * rooms export now works correctly
 * updated json helper files
 * added export of rooms to a structured by buildingNb data structure
(hackish)
- updated ui:
 * filters externalized to seperate json file
 * filter structure modified to have rooms/buildings as first level key
 * added import/loading of external json files into main custom element
 * updated filtration code to match the above changes
 * added removal of empty keys to filtration code