Rewrite test_createChallenge_decryptedAnswerMatches() unittest.
Rewrite test_createChallenge_decryptedAnswerMatches() unittest.

 * CHANGE GimpCaptchaTests.test_createChallenge_decryptedAnswerMatches()
   unittest to also check embedded timestamp.

mmaker/bridgedb,pagea/bridgedb,pagea/bridgedb,mmaker/bridgedb