- add macros.ghc for new Haskell Packaging Guidelines (#460304)
    - add selinux file context for unconfined_execmem following darcs package
    - generate docs following upstream's instructions, now under docdir/ghc
    - setup docs building in build.mk
    - drop requires chkconfig
    - do not override __spec_install_post
    - no longer need to remove network/include/Typeable.h
    - remove runhaskell since it is an alternative