So when PACKET_SDL_EVENT was SDL_USEREVENT, things worked fine in the
main loop it would see SDL_USEREVENT and send it off to my_SDL_UserEvent.
But when I started adding more events, the SDL_UserEvent paradigm given
in the SDL Wiki stopped working.
The example here is broken: https://wiki.libsdl.org/SDL_AddTimer
The example here is working and "correct": https://wiki.libsdl.org/SDL_UserEvent
All SDL_RegisterEvents is increase a static counter. SDL doesn't
actually use these events anyway. It's purely symbolic, as far as I can tell.
So anyway. Now events work after a bunch of debugging.
SHADER_PROGRAM_REFRESH is the second user event I've done.
The ShaderProgram runs an SDL_TimerID that looks at mVertexPath,
mGeometryPath if present, and mFragmentPath. mVertexPath and
mFragmentPath are required by Compile3ShaderBuffers.
In the future I'd like to change the way this class behaves.
Server listens correctly with threads and stdin reader thread.
Client does nothing currently gutting UDP_Write for a UDPbase class
introduced in this commit.
