Resolve "Use the shuffled cardset "Zugang" for the card visibility"

Closes #1056

See merge request arsnova/flashcards!1225

Resolve "Card count for shuffled sets in word cloud wrong or missing"

Closes #1050

See merge request arsnova/flashcards!1219

Merge branch '1051-add-a-sass-variable-to-control-the-margin-between-the-card-navigation-and-card-itself' into 'staging'

Resolve "Add a Sass variable to control the margin between the card navigation and card itself"

Closes #1051

See merge request arsnova/flashcards!1217

Merge branch '1049-shuffled-cardset-change-the-display-of-authors-in-the-word-cloud-info-page' into 'staging'

Resolve "Shuffled cardset: Change the display of authors in the word cloud info page"

Closes #1049

See merge request arsnova/flashcards!1215

Resolve "Add a constrat mode toggle button for the presentation view"

Closes #1045

See merge request arsnova/flashcards!1212

Merge branch '1005-new-style-of-landing-page-start-with-the-demo-card-set-then-show-the-word-cloud' into 'staging'

Resolve "New style of Landing Page: Start with the demo card set then show the word cloud"

Closes #1005

See merge request arsnova/flashcards!1189

Merge branch 'staging' into '1005-new-style-of-landing-page-start-with-the-demo-card-set-then-show-the-word-cloud'

# Conflicts:
#   imports/ui/impressum/impressum.html
#   imports/ui/welcome/welcome.html

Resolve "Special branding for different deployments"

Closes #1030

See merge request arsnova/flashcards!1200

fix english title in i18n

See merge request arsnova/flashcards!1196

Resolve "Level "Allgemein" not selectable"

Closes #965

See merge request arsnova/flashcards!1156