Failing test showing StateManagers using mixins to get some of their states have unexpected behavior
scope cached state transition hashes to the state manager class, so extending and mixins work with StateMangers as expected
Merge pull request #2473 from raycohen/state-manager-issue

Scope state transition cache to the state manager class
Do not build the docs for `.cachable`. Fixes #2329.

Also, drop a lingering use of the function in tests.
Do not flag .generateController for documentation.
Merge pull request #2496 from mixonic/cacheable-documentation

Drop .cacheable documentation
Fixes Ember.EnumerableUtils without extend prototypes