gcc 4.2.0 freebsd port

Lately, I've been working with Lev Serebryakov (lev@) to update the following ports to more modern versions:

• devel/mingw32-bin-msvcrt to w32api 3.9 and mingw-runtime 3.12
• devel/mingw32-binutils to a v2.17.50 snapshot
• devel/mingw32-gcc to 4.2.0

Now, I know that some people are going to argue that there is not even GCC 4.x in Cygwin yet. Well, I know that too, but I took the time to get the 4.2.0 cross compiler build, and it works very well for me. I felt that it would be a worthy addition to the ports tree to bring it in-sync with the rest of our GCC ports.

Talking with Lev, I think that we're going to add an OPTIONS= framework to the port, to allow the user to selectively enable/disable compilers and features at their whimsy.