feat: Add disablePluralKeyChecks option

Author: cletusw

README.md

@@ -40,7 +40,8 @@ messages['ordinal-example']({ N: 1 });
 
 ## Options (passed as [query parameters](http://webpack.github.io/docs/using-loaders.html#query-parameters))
 
-* `locale` The [CLDR language code](http://www.unicode.org/cldr/charts/29/supplemental/language_territory_information.html) to pass to [messageformat.js](https://messageformat.github.io/messageformat.js/doc/MessageFormat.html). Defaults to `en`.
+* [`locale`](https://messageformat.github.io/messageformat.js/doc/MessageFormat.html#MessageFormat) The [CLDR language code](http://www.unicode.org/cldr/charts/29/supplemental/language_territory_information.html) to pass to [messageformat.js](https://messageformat.github.io/messageformat.js/doc/MessageFormat.html). Defaults to `en`.
+* [`disablePluralKeyChecks`](https://messageformat.github.io/messageformat.js/doc/MessageFormat.html#disablePluralKeyChecks) By default, messageformat.js throws an error when a statement uses a non-numerical key that will never be matched as a pluralization category for the current locale. Use this argument to disable the validation and allow unused plural keys. Defaults to `false`.
 
 ## License
 

index.js

@@ -5,7 +5,11 @@ module.exports = function(content) {
   var query = loaderUtils.parseQuery(this.query);
   var locale = query.locale || 'en';
   var messages = (Array.isArray(this.inputValue) && typeof this.inputValue[0] === 'object') ? this.inputValue[0] : this.exec(content);
-  var messageFunctions = new MessageFormat(locale).compile(messages);
+  var messageFormat = new MessageFormat(locale);
+  if (query.disablePluralKeyChecks) {
+    messageFormat.disablePluralKeyChecks();
+  }
+  var messageFunctions = messageFormat.compile(messages);
 
   this.cacheable && this.cacheable();
   this.value = [ messageFunctions ];