added prod languages

package.json

@@ -45,7 +45,26 @@
   "homepage": "https://github.com/mozilla/send/",
   "license": "MPL-2.0",
   "repository": "mozilla/send",
-  "availableLanguages": ["en-US"],
+  "availableLanguages": [
+    "en-US",
+    "zh-TW",
+    "zh-CN",
+    "cs",
+    "fr",
+    "fy-NL",
+    "de",
+    "hu",
+    "it",
+    "ja",
+    "kab",
+    "ms",
+    "pt-PT",
+    "sk",
+    "dsb",
+    "hsb",
+    "sv-SE",
+    "cy"
+  ],
   "scripts": {
     "build": "npm-run-all build:*",
     "build:upload": "browserify frontend/src/upload.js -g uglifyify -o public/upload.js",