release 2.0 beta (#3722)

* remove twitter link
* remove WIP file
* adjust release draft message
* reset code coverage threshold back to 0.5
* changed wordings
* re-activate wizard for fixture accounts
* fix repo url and license
* license identifier
* bump version
* moved Kimai 1 import command from core to plugin
* do not traverse into invoice template subdirectories (#3735)
* fix branch alias
* composer update
* switch language on wizard select
* new twig function to create qr code
* fix daily stats in timesheet listing
* improved html invoice templates

src/Entity/User.php

@@ -439,6 +439,11 @@ class User implements UserInterface, EquatableInterface, ThemeUserInterface, Pas
         return (bool) $this->getPreferenceValue('export_decimal', false, false);
     }
 
+    public function getSkin(): string
+    {
+        return (string) $this->getPreferenceValue(UserPreference::SKIN, 'default', false);
+    }
+
     public function setTimezone(?string $timezone)
     {
         if ($timezone === null) {