adding a fallback for en_GB and en_US

public/src/modules/translator.js

@@ -47,6 +47,11 @@
 		// Load the appropriate timeago locale file, and correct NodeBB language codes to timeago codes, if necessary
 		var	languageCode;
 		switch(config.userLang) {
+			case 'en_GB':
+			case 'en_US':
+				languageCode = 'en';
+				break;
+
 			case 'cs':
 				languageCode = 'cz';
 				break;