Fix rss reader dates

Partial fix for #896

![0-options](https://cloud.githubusercontent.com/assets/928116/4208975/cedb68b0-3864-11e4-8e8a-696d04e34ce6.png)

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![1-default](https://cloud.githubusercontent.com/assets/928116/4208977/d36e5b62-3864-11e4-8cd0-5fd4938092eb.png)

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![2-custom](https://cloud.githubusercontent.com/assets/928116/4208979/d83704f0-3864-11e4-9ed3-d1266e498dfd.png)