am 8bec09ee: add \'extras\' mechanism to OTA and signing tools

Merge commit '8bec09ee7264160e4e08973a0efcc6bd2c898925' into eclair-plus-aosp

* commit '8bec09ee7264160e4e08973a0efcc6bd2c898925':
  add 'extras' mechanism to OTA and signing tools