Auto merge of #1225 - GavinJoyce:gj/diff-style, r=acorncom
Auto merge of #1225 - GavinJoyce:gj/diff-style, r=acorncom

removed diff style

fixes: https://github.com/emberjs/ember.js/issues/12913
slack chat: https://embercommunity.slack.com/archives/documentation/p1454619920000419

**before:**

![image](https://cloud.githubusercontent.com/assets/2526/12830441/414a5544-cb87-11e5-87a4-cbd674cd417c.png)

**after:**

![image](https://cloud.githubusercontent.com/assets/2526/12830446/47d888fe-cb87-11e5-808b-3e4d39fc8f9b.png)

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