X: move keyboard registration
gfx: remove private palette support that no one uses these days
gfx: rename put_image to refresh_rect
gfx: simplify palette handling
vgaemu: dont use dac index as dirty flag
gfx: avoid using remap_obj from rendering backends

The regression of that patch is that the X backend no longer looks
into the resizing properties.
gfx: move some private stuff to render_priv.h
sdl: avoid recursive leavedos on videomode failure
console: make graphics subsystem a plugin
make term subsystem a plugin
hide private exports for X and SDL plugins
make hgc a video plugin
make Video_none private
make console a video plugin
move console stuff to plugins
Merge branch 'vid_tweaks' into devel
fix few regressions
enable interrupts while processing video memory
pcm: fix a few races
ser: allow non-tty ports, handle them as fifo