Use pushd instead of cd.
Fix shareed object targets.
Fixes for cl.
[Issue #123] Windows builds should compile even with sh.exe in path.
[Issue #122] Simplified nmake build files. Does not call utilities\make in src\Makefile.
Clean ad2csv object files.
Make sure contrib.h is copied.
Add contrib/include to version control.
Opss copy headers.
VC build improvements.
Update build files for VC
Rename cl.mak to Makefile.
Fix contrib build paths for vc.
[Issue #101] mingw.mak builds contrib libraries by default.
Cleaned up various makefiles and added GNUmakefiles for user contributed libraries