Detect how to display pdf files

Closes: #1099

modules/webapp/src/main/elm/Messages/Data/PdfMode.elm

@@ -0,0 +1,39 @@
+{-
+   Copyright 2020 Eike K. & Contributors
+
+   SPDX-License-Identifier: AGPL-3.0-or-later
+-}
+
+
+module Messages.Data.PdfMode exposing
+    ( de
+    , gb
+    )
+
+import Data.Pdf exposing (PdfMode(..))
+
+
+gb : PdfMode -> String
+gb st =
+    case st of
+        Detect ->
+            "Detect automatically"
+
+        Native ->
+            "Use the browser's native PDF view"
+
+        Server ->
+            "Use cross-browser fallback"
+
+
+de : PdfMode -> String
+de st =
+    case st of
+        Detect ->
+            "Automatisch ermitteln"
+
+        Native ->
+            "Browsernative Darstellung"
+
+        Server ->
+            "Browserübergreifende Ersatzdarstellung"