XCode 64bit sample application

I was able to get an XCode sample app compiling in 64-bit. I did have to make some modifications to the GStreamer framework itself to get it compiling. These changes are summarized at the top of the sample application's .cpp file. I couldn't get it to play h264-encoded mov files correctly--they play, but there seems to be something wrong with the pixel order. This is true whether you use the pixel buffer or the osxvideosink, so I'm guessing it has something to do with the ugly plugin itself. It's pretty rough, but is at least a POC/RFC.