Make sure that aws gem is set up right.

[simonv3]

With a lot of the recent updates of the gems #801 #802 #803 and updating paperclip we needed to update to a new version of the aws gem.

But removing the old aws-gem and replacing it with aws-gem-rails caused our guide saving to spit out a paperclip error.

Sort out what the right thing to do here is. Unfortunately at the moment I'm incredibly unknowledgeable about the aws situation.