The console renderer now renders to a text buffer, which can be implemented
on any device, whether it's the VGA text buffer or a bitmap graphics device
with font rendering. This replaces the older code that could only render to
a VGA framebuffer and where the input parsing was tightly coupled with the
device rendering phase.
Caps lock now works as caps lock, not as shift lock.
This new design will allow implementing a working tty, such that stdin is
the only way to access the keyboard, instead of the current hacky way of
using a special system call to read from the keyboard.
Added a new system header file <sys/keycodes.h> defining the constants for
every key on the keyboard. This will be used in future APIs.
The main change is to split the keyboard driver into a class that reads
from the keyboard, while another class handles the translation into
printable characters (if possible). This allows a terminal driver based
on logical key presses and printable characters, instead of a terminal
driver based only on unicode-ish codes.
