clone query object

src/pagination.js

@@ -1,6 +1,7 @@
 'use strict';
 
 var qs = require('querystring');
+var _ = require('underscore');
 
 var pagination = {};
 
@@ -37,10 +38,10 @@ pagination.create = function (currentPage, pageCount, queryObj) {
 		return a - b;
 	});
 
-	queryObj = queryObj || {};
-
 	delete queryObj._;
 
+	queryObj = _.clone(queryObj || {});
+
 	var pages = pagesToShow.map(function (page) {
 		queryObj.page = page;
 		return { page: page, active: page === currentPage, qs: qs.stringify(queryObj) };