Merge branch 'feature/mongo_2.6.5_expressions_SetDifference' of https://github.com/RiveraGroup/mungedb-aggregate into feature/mongo_2.6.5_expressions_SetDifference

lib/pipeline/expressions/SetDifferenceExpression.js

@@ -10,7 +10,7 @@
  **/
 var SetDifferenceExpression = module.exports = function SetDifferenceExpression() {
 
-	if (arguments.length != 0) throw new Error("SetDifference constructor must be called with no args");
+	if (arguments.length !== 0) throw new Error("SetDifference constructor must be called with no args");
 
 	base.call(this);
 }, klass = SetDifferenceExpression,