add ssl verify for OAuth2

If you are running an oc-id instance that has a self-signed cert, the OAuth dance will fail because of a Faraday error. This lets you set an environment variable to turn off SSL verification, which makes it work.

`CHEF_AUTH2_VERIFY_SSL` is set to `false` in this repo's .env by default (because if you're running in development it's more likely that your oc-id is not going to have a real cert), but in the cookbook it is set to `true` by default.

See opscode-cookbooks/supermarket#53 for the part that goes in the cookbook.

Also changes rubocop to allow hashrockets.