Allow custom Graph colors (#76)

lib/util.js

@@ -100,6 +100,18 @@ exports.getCurrentTimeMs = function() {
     return new Date().getTime();
 };
 
+exports.stringToColor = function(base) {
+    var hash;
+
+    for (var i = base.length - 1, hash = 0; i >= 0; i--) {
+        hash = base.charCodeAt(i) + ((hash << 5) - hash);
+    }
+
+    color = Math.floor(Math.abs((Math.sin(hash) * 10000) % 1 * 16777216)).toString(16);
+
+    return '#' + Array(6 - color.length + 1).join('0') + color;
+}
+
 exports.setIntervalNoDelay = function(func, delay) {
 	var task = setInterval(func, delay);