Integration with appraisal

Hey,
So I took a look at it. I think main source of the problem was that you generated rails 4.0 app, it would probably be easier to upgrade generated 3.1 or 3.2 but I downgraded dummy to be compatible with 3.1 - 4.0

[Edit] You will probably have some suggestions, even though it is an early version. Integration with Appraisal should, however, not really change much, if at all. It is mostly implemented similarly to many other repos.