deprecate chef_api and site from the Berksfile DSL
add 'source' to Berksfile DSL for adding Berkshelf api sources
add Berkshelf::APIClient for communicating to API Servers

an API server will now start and run with no builders started during the test suite
you can add to the cache with the helper methods included by Berkshelf::Rspec::BerksAPIServer
resolver will now build and read a universe to determine a solution
fix issue where all locations were not required properly
add Berkshelf::Source