Add gitignore for Ruby based on GitHub template.
Add LICENSE file and update readme.
Add client to process a simple request to Nike+ API.

- Add config YAML file to handle configuration.
- Update readme with configuration notes and how to run the client.
Allow additional endpoints and better config validation.

- Use variable to check all configuration variables and then error out after checking all cases.
- Add the three endpoints available via the Nike+ API.
- Add ability to select the endpoint to be used via command line arguments.
Refactor config setup and validation into methods.

- Create methods to get access_token and app_id.
- Create method to validate access_token, app_id, and check command line arguments are passed in.