def theme_yaml(key = nil)
      if File.exists?("#{Rails.root}/app/views/themes/#{current_theme}/theme.yml")
        theme_yaml = YAML.load(File.read("#{Rails.root}/app/views/themes/#{current_theme}/theme.yml"))
        theme_yaml[key]
      else
        'html.erb'
      end
    end
def theme_yaml(key = nil)
      if File.exists?("#{Rails.root}/app/views/themes/#{current_theme}/theme.yml")
        theme_yaml = YAML.load(File.read("#{Rails.root}/app/views/themes/#{current_theme}/theme.yml"))
        theme_yaml[key]
      else
        'html.erb'
      end
    end
get a value from the theme yaml file by the key
 Params:
 +key+:: YAML key of the value that you want to retrive