pkgconfig in stdenv is only used for mingw, not for cygwin. So
pkgconfig will be build on cygwin from source. This will fail because
of the ? in the filename.
svn path=/nixpkgs/trunk/; revision=8152
* Make builders unexecutable by removing the hash-bang line and
execute permission.
* Convert calls to `derivation' to `mkDerivation'.
* Remove `system' and `stdenv' attributes from calls to
`mkDerivation'. These transformations were all done automatically,
so it is quite possible I broke stuff.
* Put the `mkDerivation' function in stdenv/generic.
svn path=/nixpkgs/trunk/; revision=874
