Rewrite system specs with OHAI integration testing infra.
Refactor the runner class.
Make sure require_plugin() checks v6 plugins first.
Use partial paths as keys in the v6 dependency solver.
Handle AttributeNotFound exception correctly.
Remove the left over pry statements.
Merge pull request #242 from opscode/OC-10251

OC-10251: Comments and minor changes for Nitpicks