Merge pull request #4 from barsoom/master

Import barsoom improvements.
1.9 -> 1.8 syntax.
Add ruby 2.0 to travis build.
Update compatibility text.
Documenting activemodel gotcha.

Found it when I tried the quick test gist.
Copy
Adding our latest app to the "Apps" section.
Merge pull request #5 from barsoom/master

Pull in barsoom changes
Moving unused method from Entity::Core to Entity.

Making it more clear what role Entity::Core plays.
Upping version.