code: Rename a variable with a conflicting name.

A variable named 'time' might raise conflicts with recent libc. This
variable is renamed.
build: Add support for ARM targets.

FIXME: Please go to autotools...
code: Disable the X11 init plumbing.

Remove all code in gfx init related to X11, as we are ditching the
render engine from the core engine.
code: Add a macro to remove warnings due to unused variables.

FIXME: Move this file to include/b_unused.h
code: Dump the video framebuffer to the console.

This is ASCII-DOOM into the console! The framebuffer is converted
from a 256 colors palette to a 16 ascii-characters palette.

NOTE: It seems printing colors to the console is time consuming,
resulting in a non-fluid refresh rate. Instead of printing 16
colors (ANSI) symbols to the console, the palette is switched to
black & white symbols, trying to create the illusion of a grayscale.