Remove unused translation string (#1708)

* Update CHANGELOG.md

* remove unused "old" translation string

translations/CHANGELOG.md

@@ -86,5 +86,7 @@
 * + duration
 * - removed: delay
 * + create_anouncement_success
+## 2017/11/03
+* - removed: old
 ## 2017/11/04
 * + nsfw_content

translations/en-us.all.json

@@ -1723,10 +1723,6 @@
     "id": "large",
     "translation": "large."
   },
-  {
-    "id": "old",
-    "translation": "old"
-  },
   {
     "id": "optional",
     "translation": "Optional"