updated german translation

one ScrollUp has to be ScrollDown

src/PicView.Core/Config/Languages/de.json

@@ -288,11 +288,11 @@
   "ScrollAndRotate": "Scrollen und drehen",
   "ScrollDirection": "Scrollrichtung",
   "ScrollUp": "Nach unten scrollen",
+  "ScrollDown": "Nach unten scrollen",
   "ScrollToBottom": "Zum Ende scrollen",
   "ScrollToTop": "Zum Anfang scrollen",
   "ScrollToZoom": "Mit Mausrad zoomen, mit Strg navigieren",
   "ScrollUp": "Nach oben scrollen",
-  "ScrollUp": "Nach unten scrollen",
   "Scrolling": "Scrollen",
   "ScrollingDisabled": "Scrollen deaktiviert",
   "ScrollingEnabled": "Scrollen aktiviert",
@@ -385,4 +385,4 @@
   "_3Star": "3 Sterne",
   "_4Star": "4 Sterne",
   "_5Star": "5 Sterne"
-}
+}