Decouples CacheManager from CacheBuilder

CacheBuilder does NOT get started

All the tests are passing/pending
Performs full cookook fetch/diff cycle with no data
Adds SiteConnector for connecting to opscode community site and pulling cookbook data
Adds #cookbooks to opscode cache_builder to pull cookbooks from community site
Merge branch 'master' into cache_builder
Adds #cookbooks to dependency cache to retrives a list of remote cookbooks
Implements diffing and cache updating. Updated expected structure of cache to match cache_manager #add and #remove
Stubs out metadata retrieval and moves changes to supervision group into run! because of celluloid 0.14 upgrade

Fixes some small bugs
Use instance so that NotStarted error will be raised
Use pool_link to link the SiteConnector pool to the PoolManager
Mock out connections via partial mocking attr_readers instead of injecting them via initialize
Downloads the tar package from the community site and pulls its
metadata.rb information
Small refactors and some testing
use write instead of print to avoid nil in empty files
remove empty file
Fixes single letter variable name
Merge pull request #2 from RiotGames/cache_builder

Opscode Cache builder