Design tweaks to the tree per #11540
Further design tweaks per #11540, including context menu styling per #11551
Changed a German phrase

* origin/pr/11557:
  Changed a German phrase
Fix: Preserve order of selected values in multiselect TV
Changed a few english translations
Proposed UI fix for #755
Design tweaks

* origin/pr/11556:
  Further design tweaks per #11540, including context menu styling per #11551
  Design tweaks to the tree per #11540
Preserve order of selected values in multiselect

* origin/pr/11568:
  Proposed UI fix for #755
  Fix: Preserve order of selected values in multiselect TV
Remove core/docs/tutorials

Closes #11573
Translated changed phrases in topmenu.inc.php to German