Update Haskell example to zeromq-haskell v.0.5

Motivation: the previous (current) code is not working with the latest version of zeromq3-haskell (at least from 0.4). And IMHO quite a few examples have never been working.

I have converted most examples to use the monadic layer introduced from version 0.3. I left some to use ZMQ3  so both style co-exist.

Polling works with the monadic layer since 0.5

All updated examples have been tested manually with success.

PS: I have not been able to update "interrupted" so it makes so sense in Haskell. In the current version (signal catched), the receive call does not exit (so it keeps waiting for a send).

Any further improvements/updates are welcomed. I might make so more cleanup later on.