Added comments

Added comment to clarify obscure method

app/helpers/application_helper.rb

@@ -61,6 +61,8 @@ module ApplicationHelper
     "#{root_url.chomp("\/")}#{url}"
   end
 
+  # This method is used to embed the font inside CSS when the asset is precompiled. It is required in order to allow
+  # wkpdfhtml embeding custom fonts inside the PDF.
   def self.asset_data_base64(path)
     asset = (Rails.application.assets || ::Sprockets::Railtie.build_environment(Rails.application)).find_asset(path)
     throw "Could not find asset '#{path}'" if asset.nil?