Use docker & fig in development

1. Install Docker & Fig, if you are using Windows or Mac, you also need to install Boot2docker.
2. sudo fig up -d db ( This downloads the MySQL image).
3. sudo fig run web rake db:setup
4. sudo fig up (This downloads the Ruby image).
5. Open your browser at http://localhost:3000 (if you're using Boot2docker, replace localhost by the output of Boot2docker ip).