Adjust line height of post h1 elements.

On a mobile device, the heading of the posts would overflow and the text would
overlap.

Adjusted the h1 elements to have a line height of 1, so as to remedy this.

_Side note: I checked h2-h6 elements, and they did not have the same issue._

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### Before:
![screen shot 2014-07-01 at 10 08 15 pm](https://cloud.githubusercontent.com/assets/1141717/3451416/883783ee-0196-11e4-9663-f94e80037ef1.png)

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### After:
![screen shot 2014-07-01 at 10 08 01 pm](https://cloud.githubusercontent.com/assets/1141717/3451418/8e1626b2-0196-11e4-89a0-2f2c63ff3557.png)