patch applied (cabal): Various minor improvements to c2hs support

[Duncan Coutts]

Tue Apr 13 01:32:52 PDT 2010  Duncan Coutts <duncan at haskell.org>
  * Various minor improvements to c2hs support
    - ticket #327: require c2hs version 0.15 as minimum
    - ticket #536: pass c2hs include dirs of dependent packages
    - ticket #537: pass c2hs location of gcc -E

    M ./Distribution/Simple/PreProcess.hs -12 +32

View patch online:
http://darcs.haskell.org/cgi-bin/darcsweb.cgi?r=cabal;a=darcs_commitdiff;h=20100413083252-adfee-37e18ac6f0c18e9db9e030816ea2728585af4827.gz