def sign_package(package_file)
      success = false
      timestamp_servers.each do |ts|
        success = try_sign(package_file, ts)
        break if success
      end
      raise FailedToSignWindowsPackage.new if !success
    end
def sign_package(package_file)
      success = false
      timestamp_servers.each do |ts|
        success = try_sign(package_file, ts)
        break if success
      end
      raise FailedToSignWindowsPackage.new if !success
    end
Iterates through available timestamp servers and tries to sign
 the file with with each server, stopping after the first to succeed.
 If none succeed, an exception is raised.