Refactor roles/run_list and fix RVM permissions.
Merge pull request #21 from rjackson/refactor_roles_and_fix_rvm_permissions

Refactor roles/run_list and fix RVM permissions.
Update README.md
Update README.md
Update README.md
Update README.md
Add region as option, and update tests to reflect.
Merge pull request #22 from rondale-sc/add_region_to_available_ec2_params

Add region as option, and update tests to reflect.