An error "undefined method `add_internal_loads'" caused by a nil/empty @load_system.

BSync ver: v0.2.1;
EDV branch: rubocop;
Data: sf utility meter data (attached).
monthlyenergy_bricr_filtered.csv

Root cause:
@load_system is not assigned in facility.rb read_and_create_initial_systems for having a non-empty systems_xml.element.

Steps to repeat:

1. save monthlyenergy_bricr_filtered.csv under <root_dir>/data/example;
2. rake format_data[sf];
3. rake generate_xmls;
4. rake add_measured_data;
5. rake generate_control_csv;
6. rake simulate_batch_xml.

No simulation files generated in workflow_results/Simulation_Files directory.