[Distutils] distutils and objective-c

in order to get my project running on OSX, it's going to need a small bootstrap in objective-c. this is to help setup the cocoa environment. everything is working fine with that, the only problem is if files with the ".m" or ".mm" extension are listed in the "Setup" file (read by the read_setup_file) it doesn't recognize these extensions. we've just hacked up the read_setup_file to treat .m and .mm as regular source files and pass them along to the compiler with the rest of the .c files. this probably can't be changed in time for the python-2.2 release, eh?