Field borders

Makes text fields look a bit nicer when on a colored background.

Before:
![before](https://cloud.githubusercontent.com/assets/583202/3585889/c73b09a0-0c2a-11e4-9018-e8f437384a2a.png)

After:
![after](https://cloud.githubusercontent.com/assets/583202/3585892/c91db6dc-0c2a-11e4-82f6-692b1b438b58.png)

Before:
![before color](https://cloud.githubusercontent.com/assets/583202/3585895/cd861a66-0c2a-11e4-938f-664b6a156ebf.png)

After:
![after color](https://cloud.githubusercontent.com/assets/583202/3585898/d09959d4-0c2a-11e4-8b70-8a8ee52d84b5.png)