initial work for swapping ActiveModel for VariaModel

update Node and it's specs to implement new resource
update Role and it's specs to implement new resource
update Environment and it's specs to implement new resource
update Client and it's specs to implement new resource
update Cookbook and it's specs to implement new resource
update DataBag and it's specs to implement new resource
fix issue with InvalidResource error messages
fix issue regenerating private keys in Client resource
remove bits that are now located in VariaModel
bump required chozo version
Merge pull request #42 from reset/use-varia

remove dependency on ActiveModel