Fix Dante's review comments.

- Clean up gemspec file.
- Remove the autogenerated .rspec file.
- Fix JS defaults issue.
- Make rspec consistently use expect convention.
- lml/unconfirm#1: Removed all but one puts statement.
- Make sure rspec tests actually pass.

TODO:

- [x] Use `cache` instead of session.
This method might be deprecated in Rails 4. Not an issue now, but good to know for the future.