seed() without parameter is broken

[schmengler]

Currently the generator allows seeding the RNG with arbitrary numbers:

public function seed($seed = null)
{
    mt_srand($seed);
}

Unfortunately, leaving out the parameter does not call mt_srand() without parameters, but with null which has the same effect as mt_srand(0) (tested on PHP 5.4 and PHP 5.6)

[fzaninotto]

Right, it shouldn't accept a null value. Would you mind submitting a patch for that?

[fzaninotto]

Fixed in #543