added blur
onblur function
Update core.js
Update keyboard.js

lol you are right i didn't follow the whole conversation because I couldn't understand why it mattered since an array is an object also... but why don't we make it an empty object without the Object.prototype. By using Object.create(null);
Update keyboard.js
Update core.js
Merge pull request #454 from darbicus/master

keyisdown fix