Better styling on Groups and Repeats for readable forms

http://manage.dimagi.com/default.asp?111067

Group:
![screen shot 2014-04-30 at 10 26 07 am](https://cloud.githubusercontent.com/assets/137212/2839160/17b3259a-d042-11e3-93c2-3b98a08f5a2c.png)

Repeat:
![screen shot 2014-04-30 at 10 27 09 am](https://cloud.githubusercontent.com/assets/137212/2839161/1d461b7a-d042-11e3-9d6c-8f900f5b38a1.png)