Theming the search page when no results found.

This should handle the theming of the search page when there are no results. Had to do some digging to get to the bottom of the default no results functionality. Fixes #3497 

@aaronschachter 
We should add an `hook_update_N` function into `dosomething_notfound.install` to `variable_del` this, to keep the variable table clean.