Add a helper to aid prototyping using Placehold.it images

example_view.html.erb

<%= placeholder_image(728, 90, name: 'IAB Leaderboard ad', background_color: 'ccc') %>

prototyping_helper.rb

module PrototypingHelper
  def placeholder_image(width, height, options = {})
    # `.with_indifferent_access` allows for people using Ruby 1.9's JSON-like
    # `key: value`, syntax, which tends to create string-based, rather than 
    # symbol-based, keys
    options.merge!({
      :text => "",
      :background_color => '999',
      :color => 'fff'
    }.with_indifferent_access)
    logger.info options.inspect
    url = "http://placehold.it/#{width}x#{height}/#{options[:background_color]}/#{options[:color]}/"
    url += "&text=#{CGI::escape(options[:text])}" unless options[:text].blank?
    
    image_tag(url, alt: options[:text])
  end
  
end