Put generator param last

[singpolyma]

If the generator param goes last, then the functions can more easily be wrapped in a state monad when the user wants to do so.

The return tuple is already in the correct order for this.

[vincenthz]

for genRandomBytes or for every functions that take g as first parameter ?

[singpolyma]

Anything that is:

... -> g -> ... -> (a, g)

should be:

... -> g -> (a, g)

unless there's a very good reason for it to be otherwise, because this makes it very easy to wrap in a state monad.

[vincenthz]

it's a good suggestion. sad it's coming after the release, but i've changed that now