Merged requested to merge feature/add_gde_buildings into master
gde_buildings table stores, for each OBM building, the building's classes and their associated probabilities.
data_unit_id is necessary to be able to retrieve number of people per building and cost per building from the
In the future the code could also be modified so that the columns
probabilities are empty when the OBM building is assigned all building classes associated with the corresponding
data_unit_id, which can then be directly retrieved from the
Associated with gde-core!17 (merged).