reciprocity/ggrc-core — pull request #771 by SilasX (2013-12-14 00:07:24+00:00)
Title: Invalid spreadsheet upload crashes user session 

Per [story 61094710](https://www.pivotaltracker.com/story/show/61094710). Infrastructure for catching import exception was already in place and renders a (non-server-crashing) error message for the user; it just needed to start classifying csv importer errors as such an exception.

May need touch-up to appearance, but no longer crashes server.