Add custom languages explicitly

src/lib/custom-locales.json

@@ -0,0 +1,10 @@
+{
+    "yum": {
+        "locale": "yum",
+        "parentLocale": "en"
+    },
+    "cat": {
+        "locale": "cat",
+        "parentLocale": "en"
+    }
+}

src/lib/render.jsx

@@ -2,11 +2,17 @@ var ReactDOM = require('react-dom');
 var ReactIntl = require('react-intl');
 var IntlProvider = ReactIntl.IntlProvider;
 
+var customLanguages = require('./custom-locales.json');
+
 var render = function (jsx, element) {
     // Get locale and messages from global namespace (see "init.js")
     var locale = window._locale;
     var messages = window._translations[locale];
 
+    if (customLanguages[locale] !== undefined) {
+        ReactIntl.addLocaleData(customLanguages[locale]);
+    }
+
     // Render component
     var component = ReactDOM.render(
         <IntlProvider locale={locale} messages={messages}>