Merge branch 'docs' into 'beta'

More and more documentation

See merge request !156
5 jobs for beta in 9 minutes and 21 seconds (queued for 1 minute and 31 seconds)
Status Job ID Name Coverage
  Test
passed #15262
py37-django22

00:07:41

94.0%
passed #15263
py38-django22

00:07:08

94.0%
passed #15264
py39-django22

00:07:07

94.0%
 
  Quality Assurance
passed #15265
linters

00:01:07

 
  Docs
passed #15266
documentation

00:00:32