Update ember-dev to allow for stable builds.

Updates ember-dev with emberjs/ember-dev#30.

Details from emberjs/ember-dev#30

```
# Stable commit:

stable/ember.js
stable/daily/20130826/ember.js
stable/shas/3385bffee116a97c555b9672b64297fe283cfa5b/ember.js

# Master Commit:

ember-latest.js
latest/ember.js
daily/20130826/ember.js
shas/3385bffee116a97c555b9672b64297fe283cfa5b/ember.js

# Tagged commits:

tags/v999/ember.js
```