Created failing adapter specs for flipper-redis

- the two percentage based gates are currently not working with the
redis adapter.
- this seemed like the best location for these integration-style tests
that ensure there aren't any fatal errors (as there are now)
Fixing typecasting for percentage toggle values

- fixes previous failures, should behave exactly the same while simplifying the
logic to boot
Using struct instead of class for test
Fixing logic for Type#wrappable?

- in ruby 1.8.7 nil responds to #id
Merge pull request #14 from JackCA/fix-percentage-typecasting

Fix percentage typecasting