function buildUrl(url, items) {
            var query = '';

            plupload.each(items, function(value, name) {
                query += (query ? '&' : '') + encodeURIComponent(name) + '=' + encodeURIComponent(value);
            });

            if (query) {
                url += (url.indexOf('?') > 0 ? '&' : '?') + query;
            }

            return url;
        }
Builds a full url out of a base URL and an object with items to append as query string items.

@method buildUrl
@private
@param {String} url Base URL to append query string items to.
@param {Object} items Name/value object to serialize as a querystring.
@return {String} String with url + serialized query string items.