Fixed EWMA global leak.

The longer variable name wasn't available outside of this file and the double assignment wasn't working as intended, it was instead leaking the EWMA variable into the global scope.

stats/exponentially_weighted_moving_average.js

@@ -9,7 +9,7 @@ var M1_ALPHA = 1 - Math.exp(-5/60);
 var M5_ALPHA = 1 - Math.exp(-5/60/5);
 var M15_ALPHA = 1 - Math.exp(-5/60/15);
 
-var ExponentiallyWeightedMovingAverage = EWMA = module.exports = function ExponentiallyWeightedMovingAverage(alpha, interval) {
+var EWMA = module.exports = function(alpha, interval) {
   var self = this;
   this.alpha = alpha;
   this.interval = interval || 5000;
@@ -24,14 +24,14 @@ var ExponentiallyWeightedMovingAverage = EWMA = module.exports = function Expone
   }
 }
 
-ExponentiallyWeightedMovingAverage.prototype.update = function(n) {
+EWMA.prototype.update = function(n) {
   this.uncounted += (n || 1);
 }
 
 /*
  * Update our rate measurements every interval
  */
-ExponentiallyWeightedMovingAverage.prototype.tick = function() {
+EWMA.prototype.tick = function() {
   var  instantRate = this.uncounted / this.interval;
   this.uncounted = 0;
 
@@ -46,11 +46,11 @@ ExponentiallyWeightedMovingAverage.prototype.tick = function() {
 /*
  * Return the rate per second
  */
-ExponentiallyWeightedMovingAverage.prototype.rate = function() {
+EWMA.prototype.rate = function() {
   return this.currentRate * 1000;
 }
 
-ExponentiallyWeightedMovingAverage.prototype.stop = function() {
+EWMA.prototype.stop = function() {
   clearInterval(this.tickInterval);
 }