Add comma formatting to numbers on index view.

- Add method to handle adding commas to a number.
Add route and configuration to handle updating stats from endpoint.

- Add config.yml file to house application settings.
- Add new GET route with a simple form that checks password in config file.
- Add POST route to handle checking the form value and redirect the user if successful.
Setup resque to handle updating Steps data.

- Add resque to Gemfile for bundler.
- Create UpdateSteps class to invoke the fetch_stats rake task.
- Include UpdateSteps and rake/tasks to Rakefile.
- Enqueue UpdateSteps worker for Resque when update/steps succeeds.
Update layout and styling of update view.

- Set better layout for password textbox and submit button.
- Move header div into layout view to be reused.
- Style input type password and button type submit.
Add task to reset all-time stats and refactor connection creation.

- Refactor setup of Redis connection into a resuable method.
- Add task to reset the all-time stats.
Move redis keys into Constants class for reusability.

- Create constants class to hold the Redis keys.
- Update Sinatra application and Rakefile to use the Redis key constants.
Fix issue with setting high/low steps data.

- Ensure that the current day is not set as the high/low since the steps could still go up / down.