Merge branch '9-add-permissions-rules' into 'frontend'

...pps/maka/frontend/components/effort_types/EffortTypes.vue

.../frontend/components/grade_management/GradeManagement.vue

aleksis/apps/maka/frontend/index.js

aleksis/apps/maka/model_extensions.py

aleksis/apps/maka/preferences.py

aleksis/apps/maka/rules.py

aleksis/apps/maka/schema/effort.py

aleksis/apps/maka/schema/grade.py

aleksis/apps/maka/schema/grade_set.py

aleksis/apps/maka/util/predicates.py