Get color in the Capistrano output

Note: capistrano_colors was merged into Capistrano starting from v2.13.5. However, this requires Ruby 1.9+.

If you cannot upgrade Capistrano to 2.13.5+ (e.g. because you're still running on Ruby 1.8), simply put capistrano_colors into your Gemfile and require 'capistrano_colors' in your config/deploy.rb file.