1. If the current screen becomes invalid (ie no focus anymore), always
set the keyboard to translating mode. Otherwise, we could get stuck
because the command keystokes don't come through.
2. Catch errors in attaching to a process (X server) - For this,
implement a callback mechanism similar to the detach case. Add an
argument to report an errno via callback.
to download fonts and a per-screen call to select a font
allows easier sharing of ressources in the display driver
change the parameters to the load_font driver vector to pass all
available font information
to take a single character at a time, where the character is an "int" now.
The old interface (took a string) was never called with more than 1
char to print, and the "int" allows us to handle charsets cleanly.
The graphics device driver passes a "default attribute" for normal text
output to the wscons framework. If the emulation module needs more
attributes (for different "renditions") it can allocate them via a
callback.
For now, only the "sun" emulation makes use of it.
