Apply changes to the search settings form.

#5481 

This PR addresses https://github.com/openscholar/openscholar/issues/5481#issuecomment-47363132

Output after changes:
![selection_284](https://cloud.githubusercontent.com/assets/4497748/3422701/eaf87bfc-ff5a-11e3-863e-25ab84e00f1c.png)