Removed unused translation. Fixed untranslated string.

app/src/main/res/values-de/strings.xml

@@ -65,8 +65,7 @@
     <string name="playback_queue_remove_item">Entfernen</string>
     <string name="playback_queue_add_item">Zur Warteschlange hinzufügen</string>
     <string name="playback_queue_play_next">Als nächstes spielen</string>
-    
-    <string name="manage_add_to_playlist">Zur Playliste hinzufügen</string>
+
     <string name="manage_add_to_favorites">Als Favorit hinzufügen</string>
     
     <string name="control_toggle">Abspielen / Pause</string>

app/src/main/res/values/strings.xml

@@ -66,7 +66,7 @@
   <string name="playback_queue_add_item">Add to queue</string>
   <string name="playback_queue_play_next">Play next</string>
 
-  <string name="manage_add_to_favorites">Ajouter aux favoris</string>
+  <string name="manage_add_to_favorites">Add to favorites</string>
 
   <string name="control_toggle">Toggle playback</string>
   <string name="control_previous">Previous track</string>