Added Mac OSX XCode project with Cocoa userinterface (wrapping GLUT) for Bullet demos

Thanks to TomorrowPlus for the constribution!

Extras/AllBulletDemosOSX/main.m

@@ -0,0 +1,14 @@
+//
+//  main.m
+//  AllBulletDemos
+//
+//  Created by Shamyl Zakariya on 5/1/08.
+//  Copyright Shamyl Zakariya 2008. All rights reserved.
+//
+
+#import <Cocoa/Cocoa.h>
+
+int main(int argc, char *argv[])
+{
+    return NSApplicationMain(argc,  (const char **) argv);
+}