Log Message:
Update ghc to version 6.8.2.

The major changes in this release are adding Haskell Program Coverage (hpc)
support to the compiler, adding a debugger to GHCi, the first phase of the
base package split, and pointer tagging in the code generator (which should
mean most code improves by 10-15%, and as a result the compiler is also
faster).

Most of this upgrade was done by Paulo Matias in pkgsrc-wip.