ember.js 1.0.0-pre.4

Upgrade of Ember.js to 1.0.0-pre.4 .

Files are from : 
https://raw.github.com/emberjs/ember.js/release-builds/ember-1.0.0-pre.4.js
https://raw.github.com/emberjs/ember.js/release-builds/ember-1.0.0-pre.4.min.js

Thx :+1: