Renamed 'part_ets' into 'takes_part_in_ets'
Renamed 'co2_free' into 'free_co2_factor'
Merge branch 'ets_rename'

Conflicts:
	nodes/energy/energy_export_biogenic_waste.ad
	nodes/energy/energy_final_demand_crude_oil.final_demand.ad
	nodes/energy/energy_final_demand_electricity.final_demand.ad
	nodes/energy/energy_final_demand_network_gas.final_demand.ad
	nodes/energy/energy_final_demand_steam_hot_water.final_demand.ad
	nodes/energy/energy_import_steam_hot_water.converter.ad
	nodes/energy/energy_power_hydro_mountain_pumped.converter.ad
Bump Atlas to quintel/atlas@b555020

Renames some node attributes