Form validation i18n

## English version

![helabs_en](https://f.cloud.github.com/assets/821095/2051513/71ae10d0-8a8a-11e3-810f-a37d8e5f2747.png)

## Portuguese version

![helabs_pt](https://f.cloud.github.com/assets/821095/2051527/9ac25a12-8a8a-11e3-8ebc-d307c7c8111d.png)

Close #65