Integrating Ralf's rebase into setup.exe

[Ralf Habacker]

> Rob suggested libcygimagehlp.a for the library.
>
> Should we leave the names as is, but use -L and -I to find the right
> files instead?
>
If I remember right, this lib will be used for a cygwin based rebase and later
in the cygwin's setup application which is mingw based. So this lib must be
buildable for cygwin and mingw, isn't it ?

Additional I assume a standalone mingw based rebase would be also nice for the
mingw people.

Any comments ?

Ralf