Add Requestability object specification and implementation for determining an item's requestability
Add more examples to the NyuAleph specification
Use the Requestability object in NyuAleph to determine requestability
Remove unnecessary methods from NyuAleph; use from_aleph? to determine expansion and ajax capabilities in GetIt
Use the convoluted Item#to_h for now so that we can pass around objects
Merge pull request #17 from NYULibraries/feature/requestability_refactor

Feature/requestability refactor