Create match rules for notifications in SimpleDB

Unfortunately, using the `boto` library means we'll have to drop Python 3 compatibility for now.

Screenshots
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### `/rule/create`

![image](https://cloud.githubusercontent.com/assets/2209144/3296513/c65c45a2-f5dd-11e3-9822-eff649274d9f.png)

### `/dashboard`

![image](https://cloud.githubusercontent.com/assets/2209144/3296580/d3a4ea28-f5df-11e3-8653-f645f0152c5d.png)