update translatable strings

Author: julsemaan

client/locales/_en.json

@@ -69,6 +69,7 @@
   "Keyboard shortcuts": "Keyboard shortcuts",
   "Large": "Large",
   "Logged in as": "Logged in as",
+  "Medium": "Medium",
   "Mime type": "Mime type",
   "Moving around": "Moving around",
   "New": "New",
@@ -117,6 +118,7 @@
   "Share": "Share",
   "Show all characters": "Show all characters",
   "Show file info": "Show file info",
+  "Show print margin": "Show print margin",
   "Skip": "Skip",
   "Small": "Small",
   "Starting up application": "Starting up application",