#### Summary

It looks like latest version includes `buffer.js` on the browser bundle even if not actually used.
This makes axios bundle size **3 times bigger**, adding 22kB to the minified size (0.16.0 is 11.9 KB while 0.16.1 is 33.9kB).

#### Context

- axios version: v0.16.1

lib/utils.js
'use strict';
var bind = require('./helpers/bind');
var toString = Object.prototype.toString;
/**
 * Determine if a value is an Array
 *
 * @param {Object} val The value to test
 * @returns {boolean} True if value is an Array, otherwise false
 */
function isArray(val) {