Download processed data

Adds the processed data download links. Addresses partially https://github.com/biocore/qiita/issues/647
It was already done (see the above two lines). I don't like it neither, but we are not going to be able to get rid of that until we do the study handlers refactoring. It is already one of the things that we want to remove from the template. Right now, this is the easier way to have the system working with the minimal functionality that we want.