Remove the insertion of the abstractor_user method into the host application ApplicationController.

[mgurley]

Looks like this method is not currently being used. Maybe it was added because I thought 'one day we might need it'.

[ybushmanova]

The paper_trail gem uses "current_user" to track version history. When host application uses Aker, user_for_paper_trail has to be defined to avoid having the whole Aker::User object serialized by paper_trail. Either it should be mentioned in documentation (i.e make sure your "current_user" method can be converted to a string), or abstractor can internally use abstractor_user as user_for_paper_trail.