add l18n ability

fixes #191

js/translator.js

@@ -0,0 +1,57 @@
+/* exported Translator */
+/* Magic Mirror
+ * Translator (l10n)
+ *
+ * By Christopher Fenner http://github.com/CFenner
+ * MIT Licensed.
+ */
+var Translator = (function() {
+	return {
+		translations: {},
+		/* translate(module, key)
+		 * Load a translation for a given key for a given module.
+		 *
+		 * argument module Module - The module to load the translation for.
+		 * argument key string - The key of the text to translate.
+		 */
+		translate: function(module, key) {
+			if(this.translations[module.name]) {
+				return this.translations[module.name][key];
+			}
+			return undefined;
+		},
+		/* load(module, file, callback)
+		 * Load a translation file (json) and remember the data.
+		 *
+		 * argument module Module - The module to load the translation file for.
+		 * argument file string - Path of the file we want to load.
+		 * argument callback function - Function called when done.
+		 */
+		load: function(module, file, callback) {
+			var self = this;
+			if(!this.translations[module.name]) {
+				this._loadJSON(module.file(file), function(json) {
+					self.translations[module.name] = json;
+					callback();
+				});
+			}
+		},
+		/* _loadJSON(file, callback)
+		 * Load a JSON file via XHR.
+		 *
+		 * argument file string - Path of the file we want to load.
+		 * argument callback function - Function called when done.
+		 */
+		_loadJSON: function(file, callback) {
+		  var xhr = new XMLHttpRequest();
+		  xhr.overrideMimeType("application/json");
+		  xhr.open('GET', file, true);
+		  xhr.onreadystatechange = function () {
+        if (xhr.readyState == 4 && xhr.status == "200") {
+          callback(JSON.parse(xhr.responseText));
+        }
+		  };
+		  xhr.send(null);
+		}
+	};
+})();