Feedback when no editions are found

www.agileplannerapp.com/boards/173808/cards/8827

editors are getting confused and think that editions filter is not working. also, updated the search results title to include the classification scope that would be applied.

![screen shot 2014-12-08 at 17 12 18](https://cloud.githubusercontent.com/assets/230074/5338969/49810c64-7f00-11e4-926c-f3bcb26513bd.png)

Can we add the class `table-header` here to be consistent with other tables?