Applies rails-diff changes

- Applies changes from http://railsdiff.org/diff/v4.0.4/v4.1.4/, with
adjustments from
https://github.com/codeforamerica/ohana-api/commit/5476c9c6c718bfb200289
34014a3bd6f5418cae0 and
https://github.com/codeforamerica/ohana-api/commit/99940e1a0292b69f4a78a
b3f0f7e4c279f5caa39

- Fixes #408