This lets us get rid of m_autorelease and m_destroy and we’ll be able
to implement init_game/init_draw later, for stuff that must happen
on the render thread.

and 2) fuck the Visual Studio compiler that crashes when confused.

lagging behind.

in each class that uses it.

sub-millisecond but can be improved if we get rid of SDL timers.

joystick class, and put a header in each source file.

the game context and in the render context, and a ticker class that
takes care of the ticking.