change type text to email for email fields

Closes #611 

#### Feedback form
![screen shot 2014-09-18 at 9 56 38 am](https://cloud.githubusercontent.com/assets/1656824/4324011/22aa4d2e-3f56-11e4-9f38-a2e4e43227b0.png)

#### Email item
![screen shot 2014-09-18 at 10 05 11 am](https://cloud.githubusercontent.com/assets/1656824/4324012/27ea5c20-3f56-11e4-9867-2282503de2ff.png)