patch applied (ghc): Add more assertions

[Simon Peyton Jones]

Wed May  2 09:37:09 PDT 2007  simonpj at microsoft.com
  * Add more assertions

    M ./compiler/basicTypes/MkId.lhs -2 +2
    M ./compiler/deSugar/Check.lhs -3 +3
    M ./compiler/deSugar/DsUtils.lhs -3 +3
    M ./compiler/deSugar/Match.lhs -1 +2
    M ./compiler/deSugar/MatchLit.lhs -1 +2