refresh feedback modal (bug 1103230)

Depends on https://github.com/mozilla/marketplace-elements/pull/4

todo: validation

![screen shot 2014-12-22 at 12 04 22 pm](https://cloud.githubusercontent.com/assets/674727/5530256/af9465e6-89d2-11e4-8c88-879df4fe6efe.png)

![screen shot 2014-12-22 at 12 02 11 pm](https://cloud.githubusercontent.com/assets/674727/5530247/9ed13036-89d2-11e4-9f8f-51ae6183ac0d.png)

![screen shot 2014-12-22 at 12 03 17 pm](https://cloud.githubusercontent.com/assets/674727/5530242/934ea0b8-89d2-11e4-8621-4c52e07f3d2e.png)

z.body