Let Alea produce sequences that are not reversible to the attacker
    
    As the PRNG algorithm is publicly known, the attacker could try to
    reveal the current state of the PRNG and consequently guess future
    pseudo random numbers.
    
    This commit mixes in domain hash so that the attacker would need to know
    the domainHash to reconstruct the PRNG state. As we try to keep
    domainHash secret from the observers, this commit should make the
    guessing of the future PRNG impossible.