Removes workaround added in #97

chef-docker released v0.33, which fixes this issue and makes
this workaround unnecessary.
Merge pull request #105 from opdemand/remove_lxc_workaround

Removes workaround added in #97
Refactor builder recipe

Move the buildpacks to an attribute, and make the recipe more readable.
Add ChefSpec/RSpec skeletons and hook up to rake
Add test coverage calculation
Set default platform/version for Runner
Flesh out controller and default specs
Remove hacky check for gem removal/installation
Add ChefSpec matchers for docker
Flesh out builder spec