Update Kendrick::Core.rb

v0.9.2 Kendrick::Core

Added
- Callback::Options : strongly typed version of the callback idiom
- Callback::Options::Hash : Hash representation of the options object.
- ::Function#to_callee : syntactic sugar for converting a proc to a Callee.
- ::Symbol#to_callee : syntactic sugar for converting a symbol to a Callee.

Changed
- Updated dependency resolution to return a boolean.
- Updated observable implementation to return a boolean on notify.
- ::DataManager#load_database : now uses a cached ::Callee and callback.
- ::Callee updated to take in option hash and new Callback::Options block
- ::Callee#call will now execute :complete even if :before returns false 
- ::Callback now uses the strongly type Callback::Options object - instead of a hash
- ::Method : included Function
- ::Proc : included Function