[SDL] Cocoa window menus in 1.3

[E. Wing]

I pretty much agree with everything Christian has said. Keeping a
Window menu shouldn't hurt.

The most important thing about key presses is that the user-defined
behavior must override the the OS processing. If the user defines Cmd
as fire, and Q as jump, we don't want to see the application quit
every time the player tries to simultaneously jump and fire. (I know
we'll never hear the end of those bug reports, especially when these
projects are Windows or Linux centric and are porting over to OS X for
the first time.)

An SDL_PassEvent function as Christian describes might be interesting.
Though it might be hard to get people to use the function unless it is
useful to other windowing environments (Windows, Gnome, KDE, etc). I'm
not sure what that code looks like though in the cases where the OS
event keys don't match per-platform. (For example, does it matter that
Windows uses Ctrl and Apple uses Cmd?)

Another idea would be to automatically determine if the event was
handled or not and there was an API option to allow unhandled events
to be passed on to the OS. But I think this would require a different
API approach to event handling.

Thanks,
-Eric