[SDL] SDL mouse bug

[David Sowsy]

> There's a big problem with the BeOS API:
> 	There's no way to grab or warp the mouse.
> I've reported it as a feature request, but their list is long and I don't
> think it will be fixed anytime soon.
I don't want to nitpick...but....
That's not *exactly* true. 

set_mouse_position(int32 x, int32 y); 
is a Miscellaneous global function in the Game Kit.
So presumably you can call it, initialize it to some point
in the BView that SDL is use, and track it and reset it. 

David