Fix input padding on number fields

This branch fixes the input padding on number fields. Without this fix the number field, in particular the quantity field is truncated:

![truncated](https://f.cloud.github.com/assets/133/1480219/507e14f4-46a2-11e3-90ba-343e90953071.png)

With this fix the number field appears as you would expect:

![normal](https://f.cloud.github.com/assets/133/1480220/5c3c19a8-46a2-11e3-99cd-c279aa9e6ee1.png)