Documentation of Stateful API is headed by pure API

[alt-romes]

The start of the haddocks for System.Random.Stateful is headed by the full pure System.Random haddocks because we re-export module System.Random right at the start of System.Random.Stateful's export list.

I propose we instead re-export the pure API from the stateful module only at the end of the module.

Current version:

After proposed change:

[alt-romes]

Fix in #187

[lehins]

Ah, yeah, very good point. In random-1.2.x we've re-exported the whole of System.Random, which made it very clear:

However, in random-1.3 the stateful uniformShortByteString was deprecated and a new pure one with the same name was added. Because of this we can't re-export the whole of System.Random anymore, which screws up the haddock. I think your approach of moving it to the bottom in #187 is very nice, at least until we can remove the deprecated uniformShortByteString, which will happen in random-1.4