Update gem versions
Update .kitchen.yml to work out of the box

Things like EC2 credentials, Digital Ocean, etc should never be inside the
default .kitchen.yml. These are better served in the .kitchen.local.yml,
which defines the user's preferences and configuration options.
Merge pull request #146 from opscode-cookbooks/sethvargo/cleanup_kitchen_yml

[COOK-4286] Cleanup the Kitchen