jquery getscript en javascript nativo. FROM: http://stackoverflow.com/questions/16839698/jquery-getscript-alternative-in-native-javascript#answer-28002292
function getScript(source, callback) {
var script = document.createElement('script');
var prior = document.getElementsByTagName('body')[0];
script.async = 1;
prior.insertBefore(script, prior);
script.onload = script.onreadystatechange = function( _, isAbort ) {
if(isAbort || !script.readyState || /loaded|complete/.test(script.readyState) ) {
script.onload = script.onreadystatechange = null;
script = undefined;
if(!isAbort) { if(callback) callback(); }
}
};
script.src = source;
}
// Example:
getScript("foo.js", function() { alert("Loaded"); });