Merge branch 'master' of https://gitlab.cs.ui.ac.id/pmpl/practice-collection/2019/1606821886-practice

Exercise2

See merge request !7

Merge branch 'master' of https://gitlab.cs.ui.ac.id/pmpl/practice-collection/2019/1606821886-practice into exercise2

Merge branch 'master' of https://gitlab.cs.ui.ac.id/pmpl/practice-collection/2019/1606821886-practice into exercise2

Revert "Merge branch 'master' into 'exercise2'"

See merge request !3

This reverts commit 7292486c

Exercise2

See merge request !2

# Conflicts:
#   functional_tests.py
#   lists/tests.py
#   lists/views.py