iteratee Unqualified Data.Nullable import in Iteratee.Base

[Maciej Wos]

Greetings,

I recently switched from iteratee-0.3.6 to iteratee-0.6.0.1 and I
really like the new library structure. In particular it is nice that
Iteratee.Base is quite small so I can import it unqualified and don't
have to prefix things like Chunk, EOF, or Iteratee with "I.".

One thing I noticed though is that Data.Nullable in Iteratee.Base is
imported unqualified; this causes a conflict with null function in
Prelude. Is it a desired behavior? I think it would be much nicer if
one could import .Base unqualified without causing any conflicts.

This also applies to Iteratee.Iteratee. I've been using it unqualified
and haven't noticed any conflicts other than that with null.

-- Maciej