Upgrade pylint to 2.1.0 (#15811)

homeassistant/components/binary_sensor/bayesian.py

homeassistant/components/binary_sensor/threshold.py

homeassistant/components/calendar/todoist.py

homeassistant/components/light/group.py

homeassistant/components/sensor/min_max.py

homeassistant/components/sensor/statistics.py

homeassistant/helpers/template.py

homeassistant/scripts/benchmark/__init__.py

pylintrc

requirements_test.txt

requirements_test_all.txt