Merge branch master into branch 115-person-overview-implement-multiple-selection-for-marking-absences-as-excused-or-for-deleting

Fix GlobalPermissionModel

See merge request !172

Avoid superfluous query for previous lesson in lesson.html

See merge request !171

Simplify getting of teacher names in _generate_dicts_for_lesson_periods

See merge request !170

It has been already fetched in the view.

Use only get_teachers in full register printout

See merge request !168

get_teachers will automatically select the correct teachers
without any need for further action

Resolve "Full register shows all persons of school (but without statistics)"

Closes #153

See merge request !167

Optimize object permission queries by using django-guardian's prefetch util

See merge request !165

Merge branch '151-get_or_create-for-lesson-documentations-and-personal-notes-doesn-t-work-correctly-because-of' into 'master'

Resolve "get_or_create for lesson documentations and personal notes doesn't work correctly because of missing unique index"

Closes #151

See merge request !166

Resolve "[SQL] Query for person statistics in week overview takes very long"

Closes #149

See merge request !164

Translations update from Weblate

See merge request !160

Jonathan Weth authored 4 years ago and Jonathan Weth committed 4 years ago

Currently translated at 100.0% (250 of 250 strings)

Translation: AlekSIS/AlekSIS-App-Alsijil
Translate-URL: https://translate.edugit.org/projects/aleksis/aleksis-app-alsijil/de/

Resolve "[SQL] Person statistics in "My students" take very long"

Closes #150

See merge request !162

- Move filter conditions into JOIN clause
- Remove superflouos subquery for tardiness
- Remove unnecessary JOINs
  - Remove need for DISTINCT by fixing double JOIN on personal notes

Currently translated at 100.0% (250 of 250 strings)

Translation: AlekSIS/AlekSIS-App-Alsijil
Translate-URL: https://translate.edugit.org/projects/aleksis/aleksis-app-alsijil/de/

Update translation files

See merge request !161

Overview of all register objects

Closes #137

See merge request !152