Moved InchLocation's `[super dealloc]` to end

Previously, I had unconventionally put InchLocation's `[super dealloc]` call at the top of InchLocation#dealloc in order to get P001Model to be able to inform the surrogate of death early enough.  Now that the `dealloc_withModelWillDie_IMP()` swizzle is working, this is no longer needed and can cause issues with the _x and _y ivars disappearing before we get a chance to release/nil them.