Bug#965299: haskell-incremental-parser no longer buildable on many architectures.

[peter green]

Package: haskell-incremental-parser
Version: 0.4.0.2-1
Severity: serious

haskell-incremental-parser 0.4.0.2-1 added a build-dependency on libghc-rank2classes-dev (>= 1.0)
however this package is only available on four out of the ten release archictures.

Potential ways forward:

1. fix haskell-rank2classes so it builds on the remaining release architectures.
2. If the dependency is in some way optional, restrict it to the arhictures where it
    is available.
3. (last resort) declare that haskell-incremental-parser is not supportable on those
    architecutures and request that the ftp-masters remove the package and it's
    reverse-dependencies (haskell-hopenpgp and haskell-hopenpgp-tools).