darcs patch: HsTime.h should be installed

ghc encounters a compile error with flags `-package time' and `-O' because header files such as HsTime.h is not installed. Although these header files are described to be installed in .cabal file, ghc uses another mechanism to determine what files are installed. The following patch enables ghc to install header files. Thu Dec 14 00:13:46 JST 2006 mukai@jmuk.org * HsTime.h should be installed