Added proper string format tokens for 32/64 bit

I suppose there should eventually be a test to make sure my assumptions about the typedefs don't change in different SDK versions. Would something like the following be reliable?

    - (void) testTypedefAssumptions {
    #if defined(__LP64__) && __LP64__
        NSAssert(sizeof(NSInteger) == sizeof(long), @"NSInteger is not a long.");
        NSAssert(sizeof(NSUInteger) == sizeof(unsigned long), @"NSUInteger is not an unsigned long.");
        NSAssert(sizeof(CGFloat) == sizeof(double), @"CGFloat is not a double.");
    #else
        NSAssert(sizeof(NSInteger) == sizeof(int), @"NSInteger is not an int.");
        NSAssert(sizeof(NSUInteger) == sizeof(unsigned int), @"NSUInteger is not an unsigned int.");
        NSAssert(sizeof(CGFloat) == sizeof(float), @"CGFloat is not a float.");
    #endif
    }