lesser QA. Warnings-driven code maid, someclean-up.

Was trying to understand hackport more, cleaned some warnings.

don't know how to solve:

``` shell
DistroMap.hs:86:35: Warning:
    This binding for `packageIndex' shadows the existing binding
      imported from `Distribution.Client.Types' at DistroMap.hs:49:42-60
      (and originally defined
         at cabal/cabal-install/Distribution/Client/Types.hs:43:3-14)
```

other commits: upstream updates on cabal submodule with gentoo patches on forked repo. don't think they are anyhow matters.