Alter theme registry to use os_search_solr for search results

#5187 
![selection_037](https://f.cloud.github.com/assets/99186/2149378/dc7b414a-93f3-11e3-9c70-fd399ce452ab.png)
![selection_036](https://f.cloud.github.com/assets/99186/2149379/de9919c0-93f3-11e3-8d28-f75b1e68d7fa.png)