reciprocity/ggrc-core — pull request #1424 by SilasX (2014-06-06 23:33:07+00:00)
Title: Limit types mappable to Responses.

Per [72684780](https://www.pivotaltracker.com/story/show/72684780). Users not seeing Objectives and other types that get mapped to responses. They actually should not have been allowed to map them in the first place; the problem was that the mapping list was not correctly excluding those types. Corrected by replacing the `business_objects` mixin with the subset that captures the mappable objects.

This still captures the Response types, which should not be permitted so `exclude_option_types` is also extended to surgically reject them.