Coloured warnings and errors under Node.js

core/modules/utils/utils.js

@@ -12,6 +12,13 @@ Various static utility functions.
 /*global $tw: false */
 "use strict";
 
+/*
+Display a warning, in colour if we're on a terminal
+*/
+exports.warning = function(text) {
+	console.log($tw.node ? "\x1b[1;33m" + text + "\x1b[0m" : text);
+}
+
 /*
 Trim whitespace from the start and end of a string
 Thanks to Steven Levithan, http://blog.stevenlevithan.com/archives/faster-trim-javascript