Use more color in the repl, loosely inspired by TextMate's SunBurst theme

lib/util.js

@@ -59,15 +59,15 @@ exports.inspect = function(obj, showHidden, depth, colors) {
           'yellow' : [33, 39] };
 
     var style =
-        { 'special': 'grey',
+        { 'special': 'cyan',
           'number': 'blue',
-          'boolean': 'blue',
-          'undefined': 'red',
-          'null': 'red',
+          'boolean': 'yellow',
+          'undefined': 'grey',
+          'null': 'bold',
           'string': 'green',
           'date': 'magenta',
           // "name": intentionally not styling
-          'regexp': 'cyan' }[styleType];
+          'regexp': 'red' }[styleType];
 
     if (style) {
       return '\033[' + styles[style][0] + 'm' + str +