patch applied (cabal): Ask the compiler what languages it supports, when possible

[Ian Lynagh]

Sun Aug  5 10:13:23 PDT 2007  Ian Lynagh <igloo at earth.li>
  * Ask the compiler what languages it supports, when possible

    M ./Distribution/Compiler.hs -106 +65
    M ./Distribution/Simple/Configure.hs -1 +1
    M ./Distribution/Simple/GHC.hs -18 +22
    M ./Distribution/Simple/Hugs.hs -4 +7
    M ./Distribution/Simple/JHC.hs -4 +7
    M ./Distribution/Simple/NHC.hs -1 +4
    M ./Distribution/Simple/Utils.hs -4 +16