load JS async

loadJS.js

/*!
 * load JS async
 * modified order of arguments, removed CommonJS stuff
 * github.com/filamentgroup/loadJS
 * gist.github.com/englishextra/397e62184fde65d7755744fdb7a01829
 * @param {String} _src path string
 * @param {Object} callback callback function
 * loadJS(_src,callback)
 */
var loadJS=function(_src,callback){"use strict";var ref=document.getElementsByTagName("script")[0];var script=document.createElement("script");script.src=_src;script.async=true;ref.parentNode.insertBefore(script,ref);if(callback&&"function"===typeof callback){script.onload=callback;}return script;};