Forecast: Try turning off relevancy.

@nilnilnil @yegg @russellholt @moollaza Have you guys found any instances of the forecast IA returning irrelevant results for certain places? For some time we've been checking the relevancy, but it seems that it filters out more things than it does returning bad results. These didn't use to work:

![screen shot 2014-05-20 at 10 21 58 am](https://cloud.githubusercontent.com/assets/81969/3028261/8257168e-e02a-11e3-8678-4fd7450cf357.png)
![screen shot 2014-05-20 at 10 22 09 am](https://cloud.githubusercontent.com/assets/81969/3028262/825c6ad0-e02a-11e3-897c-64722e98286c.png)
![screen shot 2014-05-20 at 10 22 21 am](https://cloud.githubusercontent.com/assets/81969/3028263/825d2470-e02a-11e3-876d-ece4b184607d.png)