def include_javascripts(*packages)
      options = packages.extract_options!
      options.merge!(:extname=>false)
      html_safe packages.map {|pack|
        should_package? ? Jammit.asset_url(pack, :js) : Jammit.packager.individual_urls(pack.to_sym, :js)
      }.flatten.map {|pack|
        "<script src=\"#{pack}\"></script>"
      }.join("\n")
    end
def include_javascripts(*packages)
      options = packages.extract_options!
      options.merge!(:extname=>false)
      html_safe packages.map {|pack|
        should_package? ? Jammit.asset_url(pack, :js) : Jammit.packager.individual_urls(pack.to_sym, :js)
      }.flatten.map {|pack|
        "<script src=\"#{pack}\"></script>"
      }.join("\n")
    end
Writes out the URL to the bundled and compressed javascript package,
 except in development, where it references the individual scripts.